DOCUMENT RESUME ED 053 948 TITLE Elementary Science Curriculum, Grade 5. INSTITUTION Stoneham Public Schools, Mass. PUB DATE Nov 69 NOTE 98p. EDRS PRICE DESCRIPTORS ABSTRACT SE 012 157 EDRS Price MF-$0.65 HC-$3.29 *Curriculum Guides, *Elementary School Science, General Science, Grade 5, *Instruction, *Laboratory Procedures, Science Activities, Scientific Enterprise, *Teaching Guides This is one of a set of curriculum guides for the Stoneham Elementary School Science Program (see SE 012 153 - SE 012 158). Each guide contains a chart illustrating the scope and sequence of the physical, life, and earth sciences introduced at each grade level. For each of the topics introduced at this grade level an overview of the topic, a list of concepts to be developed, motivating ideas, suggested activities to develop each concept, a reading list, a list of supplies needed, and examples of student work sheets are provided. In most activities the teacher is expected to involve all students in experimenting and applying scientific thinking. The topics covered in the grade five guide are: the changing earth (erosion, volcanoes, and uplift) ; introductory oceanography; gravity and the laws of motion; heat; and cells, tissues, and organs. (AL)
Transcript
DOCUMENT RESUME
ED 053 948
TITLE Elementary Science Curriculum, Grade 5.INSTITUTION Stoneham Public Schools, Mass.PUB DATE Nov 69NOTE 98p.
This is one of a set of curriculum guides for theStoneham Elementary School Science Program (see SE 012 153 - SE 012158). Each guide contains a chart illustrating the scope and sequenceof the physical, life, and earth sciences introduced at each gradelevel. For each of the topics introduced at this grade level anoverview of the topic, a list of concepts to be developed, motivatingideas, suggested activities to develop each concept, a reading list,a list of supplies needed, and examples of student work sheets areprovided. In most activities the teacher is expected to involve allstudents in experimenting and applying scientific thinking. Thetopics covered in the grade five guide are: the changing earth(erosion, volcanoes, and uplift) ; introductory oceanography; gravityand the laws of motion; heat; and cells, tissues, and organs. (AL)
U.S. DEPARTMENT OF HEALTH.EDUCATION & WELFAREOFFICE OF EDUCATION
THIS DOCUMENT HAS BEEN REPRO-DUCED EXACTLY AS RECEIVED FROMTHE PERSON OR ORGANIZATION ORIG-INATING IT. POINTS OF VIEW OR OPIN-IONS STATED DO NOT NECESSARILYREPRESENT OFFICIAL OFFICE OF EDU-CATION POSITION OR POLICY.
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I
.STONEHAM PUBLIC SCHOOLS
STONEHAM, MASSACHUSETTS
ELEMENTARY SCIENCE CURRICULUM GUIDE
GRADE 5
Superintendent of Schools
Assistant Superintendent
Administrative Assistant
Supervisor of Elementary Education
Michael Scarpitto, Ph.D.
Daniel W. Hogan, Jr.
Thomas L. Wilton
Ruth E. Mayo
FOREWORD
These units were written as guides for the teachers of science.The activities suggested are given to assist the teacher inillustrating the given concepts. In some instances severalactivities are suggested for one concept. It is not expectedthat the teacher use all these activities, but only those whichwill best suit her class. In other cases the activities sugges-ted follow a particular sequence which would encompass severaldays illustrating several related subconcepts along the way. It
is not expected that the teacher stick rigidly to her curriculumguide. If deviating to include another concept, however, theteacher is advised to consult the other Stoneham Science Curric-ulum Guides to be certain that the concept is not introduced atanother grade level. The teacher is encouraged to have refer-ence materials in the classroom at all times for each unit.
Whenever possible, the teacher is expected to involve all thechildren in experimenting and encouraging application of thescientific method and thinking. This would involve the follow-ing skills:
1. to formulate hypothesis2. to reason quantitatively3. to evaluate critically4. to draw conclusions5. to select procedures6. to define problems7. to create charts and keep records8. to use equipment effectively
It is intended that the teacher will adequately adapt this guideto her own class needs.
1. The depth of the earth's crust is very small in relation to thediameter of the earth.
2. Constructional forces build up the surface of the earth and makemountains.
A. Subconcept: The enormous pressure of land and sea, pushingdown on molten magma, forces it to press up against weakspots in the earth's crust and Sometimes heave the crustinto hills and mountains.
B. Subconcept: When tremendous pressure forces magma to breakthrough the earth's crust, we have volcanoes.
C. EubconCept: Folding is a force which lifts the surface ofthe earth. In folding, forces deep within the earth pusha part of the earth's cruet sideways, causing the rockLayers to become folded.
D. kilbconce#tt An earthquake is caused by the settling andshaking doWn of the earth's crust. it is called a con-structional force because it raises the earth's surface insome places.
E. EubConceo0 Faulting, huge masses of bedrock, shifting up-wards, downwards or sideways, during movements, is a con-structional forces
3. Destructional forces are constantly wearing down the surface ofthe earth.
A. Subconceptt The greatest destructional force is water.
B. Subconcept: Frost and frozen water break up rocks by con-, traction and expansion.
C. Subconcept: Extremes of temperature break rocks.
D. Subconcept: The mountain glaciers deepen the valleys; thebroad glaciers smooth the mountains and rocky hills.
E. Subconceot: Little plants called lichens which grow onrocks give off acids Which slowly crumble the surface ofthe rocks on which they grow.
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4. Rocks are formed through the forces that wear down and build upthe earth's surface; there are igneous, sedimentary, andmetamorphic rocks:
A. sakeamtat: Igneous rocks are formed from lava and magmaflow.
B. Subcpnceut: Sedimentar rocks are formed through the depos-iting of sediments which are squeezed and cemented to-gether.
C. ,Subconcetott Metamorphic rocks are formed when heat andpressure change sedimentary and igneous rocks.
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CONCEPTS :EXPERIMENTS
The depth of the earthis crust isvery email inrelation to thediameter of the earth.
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A. Sharpen a piece, of chalk so that theend is a circle inch in diameter.Tie apiece of twine around it andmeasure. off 40 inches. Put yourfinger agaidst the 40 inch mark, atthe bottom of the chalkboard. Makea half circle. This half circle ita diagkam of half the earth. Oneinch do this diagram shows 100 mileson the earth.. The scale is one inchto 100.miles..
The chalk line, inch thick, is'therocky crust of.the earth. Thiscrust .is about 3 to 25 miles thick. .
Make a.pointed mountain, about 1/16of ancinch'high. This is the world'Ahighest peak, Mount Everest.
Erase a bit of chalk,. a little morethan 1/16 of an inch, and fill thespace with blue chalk. This is thedeepest ocean, the Pacific.
B. Use a_geologidal map to show thedistribution of mountains,. valley's,plains, etc.
CONCEPTS EXPERIMENTS
It Constructional forces build up the surfaces of the eart
A. agkmageaL The enormous prey- 1. Materials:Jura of land and sea, pushingdown on molten magma, forces itto press up against weak spotsin the earth's crust and some-times heave the crust into hillsand mountains.
B. Sub, consegt: When tremendouspressure forces magma to breakthrough the earth's crust, wehave a volcano.
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h and make mountains.
half empty tube oftoothpaste
Procedure: With the cap screwed ontight, flatten the tubeso that, the toothpasteis spread evenly inside.Now push down on thelover half of the tube.What happens to the otherend?
1. lia&ezielu, plaster of Paris, a flatliquid detergent bottlewith cap, a large tinCan.
.
Irosedum Mix a thick batter of ,
plaster of Paris and'water in the large tin'can.. Pour enough pies!.ter of Paris into thebottle so that it is'completely filled. Screwthe cap on tightly.Lay the bottle on itsside. Punch a hole inthe upper section.Prep: firmly on the bqt-tle at the other end.;Plaster of Paris (magma)will pour out of the hole(break the earth's crust.)Let the plaster of Parisharden into a "volcano."
2. Materials: toothpaste tube. .
Jloggibizu (Simpler version of aboveexperiment)With.a pin, make a holenear. the bottom of thetoothpaste tube.Press the other end ofthe tube. What do youobserve?
C. Subconint) Folding is a forcewhich lifts the surface of theearth. In folding, forces deepwithin the earth push a part ofthe earth's crust sideways,causing'the rock layers to be-come folded.
Procedure: Discuss the tremendousexplosive power of somevolcanoes. Develop thatpowerful gases in themolten rock suddenly ex-pand when released intothe air. The soft-drinkbottle contains a confinedgas. Pretend that theliquid is magma. Shakethe bottle rapidly, sev-eral times. Quickly flipoff the top. An eruptionwill take place.
Extension: Make reports on famous vol-canoes: Vesuvius, Etna,Krakatoa, Fujiyama.
Build a papier machi modelof a volcano. Make a threedimensional cone from news-paper strips and wheatpaste. Cut the cone intwo parts after it hasdried. Using poster col-ors, paint the interior ofthe volcano with the rockstrata, lava core, andother parts found inside avolcano. Label all partsof the volcano and displaymodel.
Locate major volcanoes ona world map.
1. Materials: bath towels or modelingclay.
Procedure.: Put towels folded on topof each other to repre-sent the layers of theearth. Push them in fromboth sides.
Many mountains are formedthis way. Sometimes thesea bottom is pushed upto form mountains. The
Appalachian Mountains andthe Alps are fold mountains.
D. Subconcfbit. An earthquake iscaused by the.settling and ahak-trig down of the earth's crust.It is Called a constructionalforce because it raises theearth's surface in some places.
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Make a seismo ra h
1. Materials:
Procedure:
p.
Tin can, sand, pencil,tape, table, and paper.
Suspend a large tin canfilled with sand from theceiling of the classroomor a crossbar. Tape apencil to the side of thecan as shown. Lower thecan until the pencil justtouches the table top..Slip a piece of paper un-der the pencil point.Move the table gently backand forth in a horizon-tal plane under the pen-cil and observe the traceson the paper.
Explanation: A seismograph is basi-cally a free-hanging pen-dulum: its weight holdsit steady in the verticalplane. Any horizontalmovement of the tableunder our seismograph willcause the pencil to re-cord a trace on the paper.The greater the movementof the table, the longerthe trace. The tracingsrecord the vibrations ofthe earth during an earth-quake. A seismograph canrecord some of the slight-est tremors and give warn-ings of possible earth-quakes.
I table
paper
E. Subcomal Faulting, hugemasses of bedrock shifting up-wards, downwards or sideways dur-ing movements, is a construction-al force.
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Information: When the shift is straightup and down you have a cliff. Slantedfaults result in a sloping. ridge. Hugefaults which occur on two sides producelong chunks of high land called blockmountains.
To demonstrate the different faults.
1. Materials: foam rubber and paint
Paint lines to repreeLLthe layers of the earth.
iwwirs-' -; v
Hold the rubber to show a normal fault.
.=-- .1"'"
Show a thrust fault.
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CONCEPTS EXPERIMENTS
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III pestructional Porces are constantly wearing down the surface of the earth.
A. Subconcept: The greatest de- 1. Materials:force is water.
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tray, dirt, water can,flat rocks or pebbles.
Procedure: On a tray shape a moundof dirt to represent amountain. Place severalpebbles on the top of themountain, Use a sprink-ling can to cause "rain"on the mountain. Observethe lesults.
2. Materials:
Procedure:
two milk cartons, dirt,grass seed
Plant grass seed in onecarton. When the grass isabout one inch in length,tip the cartons at aslant. Sprinkle water onthe cartons. Repeat thisprocedure for several days.Observe results.
Extension: Have class look for ex-amples of erosion in theneighborhood and schoolplayground, especiallyafter a heavy rain.
3. Materials:
Procedure:
Show pictures of the GrandCanyon to show an exampleof the cutting power of astream carrying abrasivematerials.
To show how waters smoothstones in traveling..
(rivers)
coffee can with lid, stones,.smooth and rough
Place stones in can andfill halfway with water.The students must shakethe can many hundreds oftimes. The rough atonesshould get smoother, aswell as some stones break-ing up.into small particles.
B. Subconce t: Frost and frozenwater reek up rocks by contrac-tion and expansion.
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1. Materials: two small glass jars withscrew top lids, two heavypaper bags.
Procedure: Fill one jar with waterand cap tightly. Put itand an empty capped jar -this is the control - inseparate piper bags. Placeboth in the freezer sectionof a refrigerator. The jarwith water should break, aswater is one of the fewmaterials known that ex-pands rather than con-tracts when it freezes.
C. Subconcept: Ixtremas,of temper- 1. Materials: candle, matches, clearagme-tireak rocks.. glass marble, glass of
water, pliers.
D. Subconcept: The mountain gla-ciers deepen the valleys; thebroad glaciers smooth themountains and rocky, hills.
Procedure: Hold a marble with pliersin a candle Mime for tenseconds or so, then thrustit into water. Many tinycracks will appear in themarble.
Procedure: Put a handful of the rockmixture into the milk car-ton and add enough waterto cover the mixture.Freeze the water. Thenadd another handful of themixture, cover with water,and freeze again. Continueuntil you have the cartonhalf-filled with ice con-taining the mixture ofsand, soil, gravel andpebbles.
Peel the container from theblock of ice over the clay.The clay should be in along flat piece laying inthe bottom of the pan.Mat does the block do tothe clay?
E. Subconcept: Little plantscalled lichens which grow onrocks give off acids which slow-ly crumble the surface of therocks on which they grow.
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Leave the block of ice onthe clay. Tilt the panslightly and allow theice to melt. Describe the"moraines" that areformed.
1. Materials: radish or bean seeds, pietin, plaster of Paris,paper toweling.
Procedure: Mix plaster with water tothe consistency of thickcream. It will set firm-ly after about 20 minutes.Sprinkle with radishseeds. Place several lay-ers of paper toweling ontop and keep soaked withwater. One or two water-ings a day should suffice.In a few days the tinyroots of some seeds willhave penetrated into theplaster.
a. Find pictures of lichens growingon rocks.
b. Find a rock with lichens. Scrapethe lichens off and notice thatthe top layer of rock crumbles.Scrape another section of therock to show that it crumbles,only where the lichens are. Thisis caused by chemical action.
c. Look up added information on thisplant and give a report.
d. To show how chemicals break downrocks.
2. Materials: vinegar, two small seashells or piece of lime-stone, glass container.
Procedure: Put some vinegar in thecontainer and immerse thesea shell. Have somepupils listen to the bub-bling sounds. After
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18setting for 24 hours,scrape the shell with aknife. It will crumbleand break much more eas-ily than a control shellthat has not been soakedin vinegar.
CONCEPTS EXPERIMENTS
IV Rocks are formed through the forces that wear down and build up the earth'ssurface: there are igneous, sedimentary, and metamorphic rocks.
A. Subconcept: Igneous rocks are 1. Materials: Pumice, volcanic breccia,formed from lava and magma obsidian, granite, andflows. basalt rock specimens,
hand lenses.
Procedure: Have the children recallhow lava and magma flowsbuild up the land. Rocksmade in this way are call-ed igneous or fire rocks.Relate to the word "ignite':Show the five specimens.Indicate all are of igne-ous origin, but under whatconditions were they formed?Allow time for close obser-vation. Provide two clues.
Challenge the class to find two rocksfrom the five rocks to match theseclues.
a. Small bits of lava and rock mate-rials were thrown high in the airwhen a volcano erupted. Whichrock may have been formed in thisway? (volcanic breccia)
b. Some top parts of a lava flow wereWhipped into a bubbly foam fromgases inside the lava. (Pumice)
Identify the obsidian specimen as atype of volcanic glass. This forms onand near the top surface of a lavaflow.
Just below the lava flow surface,basalt forms. Hold up this specimen.
Now identify a specimen of granite.Develop that it cools under the earth'ssurface, as when a dome mountain isformed.
B. Subconcent: Sedimentary rocks areformed through the depositing ofsediments which are squeezed andcemented together.
19Pass around hand lenses and these threerock samples for close examination.Help the children notice that obsidianhas no viewable crystals, basalt has verytiny crystals, and granite has largecrystals. Raise speculation as to whythese conditions obtain. There are somedifferences in the mineral composition.
1. Materials: Conglomerate, sandstone andshale rock specimens; Masonjar about two-thirds full ofequal portions of soli, sandand pebbles. (Put water inthe jar, shake, and allowmaterials to settle over-night before starting thisactivity).
Procedure: Have the children speculateabout what happens to thetremendous amounts of soiland rock particles whicherode and wash from the landinto the seas. Develop thatthe enormous pressure of over-laid materials graduallycauses those deeper down tobe squeezed together. Chem-icals in the water help tocement the particles to-gether.
Exhibit the materials set-tled in the Mason jar. Drawon the chalkboard a largediagram of the jar and mate-rials. Let the childrenlabel the levels of mineralcontent in order, from bot-tom to top: pebbles (and alittle sand), sand, silt, andclay. Identify the silt andclay as ordinary mud. Mate-rials like these settle inlarge bodies of water andare pressed into rocks.
Show the class the conglom-erate, sandstone, and shalespecimens. Can anyone iden-tify the jar materials whichmight, under proper condi-tions, form into these rocks?
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Before permitting identi-fications, pass around therock specimens to enableclose observations. Placesome water on the shale andhave the children smell it.(It smells like mud.) Letsomeone rub several piecesof sandstone together. Puta piece of black paperunderneath to catch thesandy fragments.
Enrichment: Let pupils confirm theirobservations through read-ing. Pebble and sand par-ticles are cemented intoconglomerate or pudding-stone; sand becomes pressedand cemented into sandstone;mud becomes shale. However,layers may not necessarilyform in this order--tt de-pends on which materialserode and settle.
C. St.:1212usgati Metamorphic rocks are 1. Materials:formed when heat andpressure change sedimen-tary and igneous rocks.
Sedimentary Rock ---->
Limestone, shale, sandstone,quartzite, marble, and slaterock specimens; wire clotheshanger, wax crayons, half-ful glass of vinegar.
Procedure:. Have your class recall howmodeling clay looks after ithas been baked in a kiln.If available, show baked andunbaked pieces of clay. De-.
velop that both sedimentaryand igneous rocks can bechanged into a third rockcalled metamorphic rock.
Granite
/ ss,
/I___- S..--
Sedimentary !____--
- ---\------,
21On the diagram point out thathot igneous rock touches sur-rounding sedimentary rock in-side the dome. The adjacentsedimentary rock is baked andchanged, almost as if it werein a kiln.
Remind your group of how theearth's surface may be folded.The tremendous pressures bend,squeeze, twist, and heat therock into changed form. Haveeveryone observe the effect ofbending a solid material. Leta child rapidly bend a wirecoat hanger back and forthabout twenty times.
Touch some wax on the X. Waxwill partly melt on contactwith the hot metal.
Bring out that the folding ofrocks also produces heat, eventhough it takes place veryslowly. The combined heat andpressure changes the rocks in-to a new and different type.
Pair the sedimentary and meta-morphic specimens;
a. Limestone can ghangeinto marble.
Will marble bubble likelimestone? Wrap a piecein some cloth and crushit with a hammer. Im-merse the crushed marblein vinegar. It shouldbubble.
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b. Shale can change intoslate. (Does wet slatealso smell like mud?)It does somewhat.
c. Sandstone can change intoquartzite.
Have children notice thedistinctness of separatesand grains has diminishedthrough the crushing ac-tion of metamorphosis.
Have pupils rUb.the pairedsamples together and alsocompare their weights ifpossible. Challenge themto explain why metamorphicrocks seem harder andheavier than the parentrocks. ('The heat andpressure have compactedthem more; they aredenser.)
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VOLCANOES
Although some volcanoes have done gteat damage, many volcanoes havealso helped build up the earth's crust. Wriie how volcanoes have helpedform the following:
1. Mountains -
2. Islands -
3. Soil -
Use resource books to fill in the formation on the following chart
NAME LOCATION ACTIVE ORINACTIVE
OTHER INTERESTINGFACTS
MAUNA LOA
! PARICUTIN
VESUVIUS
r.
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EARTHQUAKES
In books or magazines, find out about two earthquakes thathappened in the past ten years. In the table below, write the factsasked for about each earthquake. You may wish to write in your sciencenotebook other interesting information that you discover about earth-quakes.
Facts about theEarthquake
Earthquake I Earthquake II
1. When the earth-
quake happened
ov,
2. Where it was
strongest--its
"center"
3. How it changed
the earth's crust
4. The damage done
to homes and people
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ADDITIONAL STUDENT ACTIVITIES
1. Look in magazines and newspapers for pictures that show the earth's surfaceat many different places on the earth to compare and contrast and to dis-cover what changes have occurred in these places.
2. Prepare a report on the world's great caves. Where. are these huge under-ground caverns located? How were they formed? Is there any life in any ofthese caves? Include some pictures of what it is like inside a large cave.
3.. Construct a diorama of the inside of a cave. Maks the main room in yourcavern out of papier- mache'. Drip candle wax or melted crayon down the sidesof the cave to represent limestone.
4. Find out as much as you can about Project Mohole. Why is this projectimportant?
5. Suggest reading about the great "Dust Bowl" wind erosion disaster in thethirties. What caused it? What measures are being taken today to preventa recurrence?
6. Encourage children to bring in magazine pictures that feature weathering anderosion.
7. Have a child report on Parimitin, a volcano that developed in a Mexican corn-field in 1943.
8. Encourage children to gather magazine pictures of the great Alaskan earth-quake of 1964, and more recent earthquakes.
AUDIO-VISUAL AIDS
Filmstrips
Changing Surface of the Earth - 46 frames - McGraw -Hill CompanyOur E th is Changing - 67 frames Jam Handy OrganizationVolcanoes and Earthauakes - 40 frames -.Harper and RowMountains - 46 frames - Harper and RowGlaciers - 22 frames - color - Universal Ed. and'Visual Arts
FILMS
The Earth's Changing Surface - 12 min. - color -Glacier Park Studies - 15 min. - color - BaileyUnderstandina Our Earth: Row Its Surface ChangesBirth and Death of Mountains - 13 min. - color -
McGraw -Hill
- 11 min. color - Coronet.Film Assoc..
Educational Television - Channel 2 - Exploring our Earth
2f.)
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BULLETIN BOARD SIGESTIONS
I. Prepare a bulletin board, including pictures of such phenomenaas a volcanic eruption, a flood, an iceberg floating in theocean, or a geyser. Captions under pictures may be in questionform to encourage children to use books to find the answers.
2. Collect pictures for a bulletin board that illustrate variouslandforms and water bodies on the earth's surface.
3. Illustrate surface features of the earth such as volcanoes,hills, buttes, and faults.
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BIBLIOGRAPHY
Block, Marie H. Mountains on The Move, Coward - McCann, 1960.
Brandwein, Paul F. Concepts in Science, Grade 5. Harcourt, Brace andWorld, Inc., 1966.
Buehr, Walter. Volcano! William Morrow and Co., 1962.
Carin, Arthur. Teaching Science Through Discovery, Ohio: Charles E.Merrill Books, Inc.1964.
Carrington, Richard. The Story Of Our Earth, Harper & Row, 1956.
Eiby, G. A. About Earthquakes, Harper and Row, 1957.
Finch, Vernon C. The Earth and Its Resources, New York, McGraw-Hill BookCo. 1959.
Frasier, George W. Solving Problems, Singer Science Series, 1955.
Lauber, Patricia. Junior Science Book of Volcanoes, Garrard, 1965.
Navarra, John. Today's Basic Science, New York, Harper & Row,Publishers, 1967.
Sterling, Dorothy. The Story Of Cavea, Doubleday * Co., 1956.
Zim, Herbert S. What's Inside The Earth? William Morrow and Company, 1953.
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INTRODUCTION TO OCEANOGRAPHY
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OVERVIEW
Though oceanography is a young science, it has already presented man
with a host of intriguing problems and many potential solutions to world
needs for minerals and other goods. Only recently has the technology of
underwater exploration been developed. Efficient submarines are a very re-
cent development; sonar, the bathyscaphe, and the aqualung are more recent
still.
Motivational ideas:
1. Collection of books on oceanography.
2. A film, such as "The Restless Sea" put out by Bell TelephoneCompany.
3. Diving equipment on display in the room.
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CONCEPTS
1. The origin of the oceans is still controversial.
2. The ocean is in constant motion.
3. Currents are caused by the water being unevenly heated by the sun.
4. There are many substances dissolved in ocean water.
5. Evaporation is a method used to regain some of the mineral wealthfrom the ocean.
6. The greater the salinity (salt content in ocean), the greater thedensity.
7. The buoyancy of water causes objects of various sizes and shapesto float.
8. To float, an object must displace its own weight.
9. A boat, or object, will float higher in salt water than in freshwater.
10. Objects weigh less in water.
11. Water pressure is one of the problems confronting divers when theyexplore the ocean depths.
12. The greater the ocean depth, the greater the water pressure.
13. Distorted vision, caused by water, is another problem to the divers.
14. The oceans and seas have layers of cold and warm water which affectthe diver.
15. Many devices are used to help man explore the ocean.
16. Sea water is being purified to be used in irrigation and as asource of drinking water.
17. Living organisms are dependent on one another for survival in theocean.
18. The mineral wealth of the ocean is a great, but unexploited area.
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Background:
The origin of the oceans is still controversial, although certain fea-tures have been adequately accounted for. When the earth was formed somethree-five billion years ago, it was a molten ball. It cooled like a desic-cating orange, its skin becoming more and more wrinkled as the interiorshrank. In this manner the ocean basins were formed.
Another hypothesis suggests that the continents of the world are re-ceding from one another. The ocean basins are, then, created as this vastmotion takes place.
It is also.thought that the moon was formed When the earth spun off apart of its mass during the cooling period, and that the scar of that gigan-tic upheaval is the basin of the Pacific Ocean.
CONCEPTS
I The origin of the oceans is stillcontroversial
II The ocean is in constant motion.
EXPERIMENTS
A. Discuss with the class the differentways the oceans might have beenformed. Some children might doadded research and report to theclass.
B. Material: Apple, water
Procedure: Dunk the apple inwater.
Explanation: The thin film of watershows the depth of the ocean incomparison to the earth's diimeter.
A. Discuss these ideas
1. If seaweed grows on thebottom of the ocean, how doesit get to the shoreline?
2. How do seashells get to thesand?
3. If you float in the ocean,you often end up in a differ-ent place than from where youstarted. Why?
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III Currents are caused by the water A. Materials: Quart bottle, a 3" x 5"being unevenly heated by the sun. card, water, food coloring.
Procedure: Fill a quart bottlewith warm water. Add a smallamount of food coloring and mix.Fill a second quart bottle withcold water. Cover the mouth of thefirst bottle with a file card. In-vert the first bottle over the sec-ond bottle. Pull out the card frombetween the bottles. Tell thechildren to watch the direction inwhich the water flows. Repeat theexperiment reversing the positionof the bottles.
In which direction is there a greaterflow of water?
B. Pour some very hot water into a sink.Let the water be as hot as you canstand to touch. Then slowly add coldwater. Where do you find the coldwater in the sink? You could addfood coloring before you pour and seewhat happens.
Reverse the procedure, putting coldwater in the sink and adding hotwater.
Explanation: Different areas ofwater in our oceans and seas differin temperature and saltiness. Thesedifferences cause variations in thedensity of water. Dense water tendsto sink toward the bottom of theocean or sea, while less dense watertends to rise. There is a patternof ocean currents very similar to thepattern of wind currents.
IV There are many substances dissolved A. Materials: pint of sea waterin ocean water.
Procedure: Evaporate a pint of seawater to see how much salt and otherminerals it contains. You will findthat there is about one tablespoonof salt and other minerals in a pintof sea water.
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V Evaporation is a method used to re- A. Materials: Water, saltgain some of the mineral wealthfrom the ocean. Procedure: Pour a cupful of water
into a shallow pan. Add 3 table-spoons of salt. Let it stand forseveral days. Observe what happens.
B. Evaporation was used to get saltlong ago in Greece and Egypt. It isstill uomi today in Iran and Califor-nia.
Prepare a special report on howancient and modern methods differ.
Vi The greater the salinity (salt con- A. Materials: beaker, water, salt,tent in ocean), the greater the scaledensity.
Procedure: Place a beaker on ascale, weigh it, and then fill thebeaker with water. Record the weightof the water (subtract the weight ofthe beaker from entire amount). Makea red line with a crayon to indicatethe water level. Then add severaltablespoons of salt to the water anddissolve it. Record the new weight.
1. Does it weigh more now?(It will.)
2. Does it occupy more space?(yes)
3. Is it any more saline?(Yes)
4. Is it denser?(Yes)
Explanation: The salt is now insolution between the water molecules,so the water increases in volume aswell as in weight.
Density of water varies with thekinds of elements dissolved in it,as well as with the amount packedinto the same space.
The saltiness of water is calledsalinity.
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VII The buoyancy of water causes ob- A. Materials: several objects includingjecte of various sizes and shapes paper clips, marbles, bath stoppers,to float. corks, balls, bottle tops, spoons,
cans, and waxed cartons.
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Procedure: 1. Sort these objectsinto three different piles accordingto their weight--light, medium orheavy.
Test each group, observing what hap-pens to each object when you drop itinto the water. Why do some objectsfloat, while others sink? Make achart and keep a record of which ob-jects float and which sink.
2. Sort the objects asto size. Test each group and observewhat happens. Does size change anobject's capacity to float?
B. Materials,: tin can, water'
Procedure: Drop a small tin can intowater. Turn it around in differentpositions. Observe.
Remove the can and flatten it. Dropit into the water and observe. Whathappens? Has its weight changed?What has changed?
What two facts about an object mightdetermine whether it floats or sinks?
C. Materials: aluminum foil, water
Procedure: Drop a ball of aluminumfoil into the water--observe. Whatforce is working on the ball?
Flatten out the foil and shape it in-to a small. boat. Hold it over thewater and then.let it drop. What keepsthe boat afloat? The water pushedaside is called displaced water.
Push the palm of your hand down on thewater. The.upward push of the wateragainst your hand is. called buoyancy.The buoyancy of water pushes up on anobject; gravity pulls down on anobject.
To float, an object must displaceits own weight.
IX A boat, or object, will floathigher in salt water than in freshwater.
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A. Materials: large pan, tin can,spring balance, block or wood
Procedure: Place the can in thelarge pan. Fill the can to the topwith water. Wipe up any spilledwater in the large pan. Carefullyplace the wooden block in the water.The water which the block has pushedover the aides of the can is calleddisplaced water.
Weigh the displaced water. Weighthe block. Compare the two weights.
Background: This concept was dis-covered by Archimedes, a Greekscientist, over two thousand yearsago.
A. Materials: glass of water, a freshegg, salt
Procedure: Put the egg in freshwater. Observe the results.
Now dissolve as much salt as you canin the water. Stir the water care-fully. What happens to the egg whenplaced in the salt water?
X Objects weigh less water. A. Materials: spring scale, wire,various objects
Procedure:, Make a sling of wire andattach the wire to a book so that youcan place objects in the wire slingfor weighing. Weigh each object outof the water. Then weigh each ob-ject while it is submerged in waterat room temperature. Try to use ob-jects made of known materials such asiron, glass, copper, lead, silver orgold.
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Record the results:
Object and Weight out Weight inMaterial of water the water Difference
Magnet--iron 16 oz. 14 oz. 2 oz.
Try various objects made of the samematerial. Divide the weight out ofwater by the difference in weight ineach case. Is the quotient very nearlythe same in each case? Now would youexplain this?
RI Water pressure is one of the prob- A. Materials: water, sink, large roundlems confronting divers when they stopperexplore the ocean depths.
Procedure: Place the stopper in thesink drain. Fill the sink with water..Now try to remove the plug. Do youfeel any resistance? The water ispressing on the plug.
B. Discuss the experience of diving tothe bottom of .a pool. Some childrenmay have felt their ears pop, chestfeeling heavy, or a strange feelingabout the head.:
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XII The greater the ocean depth, the A.. Materials: 3 milk cartons, water, agreater this pressure. nail, tape, a large pan
Procedure: Remove the tops from thecartons. Using the nail, make threeholes in the side of one carton. Onehole should be near the bottom of thecarton, one near the middle, and onenear the top. Put tape over eachhole. Hold the carton over the panand fill the carton with water. Re-move the tape from all three holes.What happens? Why? How do you ex-plain the difference between the jetsof water?
Cut the bottom out of the other car-ton. -Tape the carton on top of thecarton you have already used. Puttape on the holes again and fill thecartons with water. Remove the tape.How do the water jets now comparewith those from the single carton?
Tape the third carton and repeat theactivity. How do the jets of waternow compare?
XIII Distorted vision, caused by water, A. Materials:is another problem to the divers.
Procedure,:
9f water.the water.
water, glass, pencil
Place a pencil in a glassLook at the pencil throughWhat.do you see?
Explanation: The pencil seems tobend because of the way light rayspass through the water. Light raysbend, or refract, when they pass fromair to water. The refraction causesobjects under water to appeardistorted.
3C
lay The oceans and seas have layers of A. The water near the surface of the
cold and warm water which affect ocean is warmer than the water deep
the diver. below the surface. The layers' of :.cold and warm water are sharplydivided Which makes it difficult forthe divers to adjust to the changesin temperature. The colder the waterbecomes, the more heat it draws fromthe body of the diver. This can causethe diver's body to become cold andnumb.
XV any devices are used to helpman explore the ocean.
Discuss the above information withthe class. Ask if they have everfelt extremely cold and possiblynumb when in the ocean.
A.. A demonstration to show how the earlydiving bells worked--the Greeks usedthis method -
Materials: glass, tank, or largecontainer of water
Procedure: Push a glass of air up-side down in a tank full of water.Tip the glass slightly.
Exclamation: The Greek diver of longago could not leave his air supplyfor any length of time. When thediver needed air, he slipped underthe bell and took a deep breath.
B. Materials: Snorkel, face mask,flippers
Procedure: Show these to the classand discuss how they would help thediver. Discuss the limitations ofnot going too deep or for too longof time.
C. The aqualung has been developed tohelp solve the problem of breathingand permitting man to dive as low as40 feet below sea level. This iscalled free diving or skin diving.
Skin diving has many advantages overhelmet diving, in which the diverwears a bulky suit and a heavy metalhelmet with windows to see through.Air is pumped through the tubesattached to the helmet. A ship is
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stationed above the diver to feedhim air and to pull him up. In hel-met diving there is always the dangerthat something may happen to the airtubes. Skin diving permits the diverto carry his oxygen with him. An-other advantage is that the skindiver can 'swim like a fish and do muchmore than the helmet diver who islimited mostly to walking.
1. Discuss the above informationwith the class.
2. Find pictures to illustrate theequipment.
3. Find additional information onWhat the skin divers have foundin the ocean.
D. Prepare a report on the small two-mansubs that are being used to explorebeneath the sea.
E. Find out about Flip, the researchvessel that can stand on end.
F. Discuss operation "sealab". Noteastronaut Scott Carpenter's involve-ment in this project as a member ofthe underwater research teams.
G. Look up information about MatthewFontaine Maury, one of the first greatoceanographers.
H. Make a chart to show various devicesused for underwater exploration. In-clude a picture of each device, thescientist or technician who made adive in the device and the depthrecorded.
I. Prepare a report on scuba diving.Interview the man at the local sport-ing goods store and ask him to show
40
the equipment used by scuba diversto the class.
J. Look up information on William Beebe,bathyscaphe, bathysphere, ConshelfIII, Deepstar, Sealab I, II, III,Alvin.
XVI Sea water is being purified to be A. Materials: salt, water, teakettleused in irrigation and as a hot plate, drinking glass, piece ofsource of drinking water. glass.
Procedure: Mix a solution of saltand water. Taste the solution to besure it is salty. Pour the solutioninto a teakettle. Boil it. Hold apiece of glass in the path of thewater vapor. Note how the vaporchanges back to water. Catch thewater in a drinking glass. Taste thewater. It should no longer be salty.
B. Find information on the distillationprocess of purifying salt water, thefreezing method.
XVII Living organisms are dependent on Discuss with class -one another for survival in theocean. Life in water is in constant search
for food. Animals often compete forthe same food. They also eat oneanother to survive. This eating pat-tern is called a food chain. Thisfood chain will end when bacteria at-taches to matter and all energy isremoved.
The salt water food chain can be illus-trated with five links. The first or-ganisms in the chain are differenttypes of one-celled green plants re-ferred to as plant plankton. Theplants manufacture food'from CO2,water, and from the sun. These plantsare eaten by small one-celled animals.These animals serve as a food sourcefor small fish such es herring. Theherring and small fish are preyed uponby cod. The next link chain can beconsidered to end with the mackerel
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shark, which eats the cod, which hasfew enemies except man.
Sooner or later everything dies. Ifit dies naturally, one-called plantsand animals may use its body for food.
A. Have children find information onplankton to discover where it growsbest. They should find that plank-ton grows best in cool waters as fardown as light can reach (400 feetabout).
B. Materials: Seaweed, water
Procedure: Obtain different kinds ofseawwed from the ocean for the chil-dren to examine. Have them look forroots and stems. Explain holdfasts.(Seaweed do not have roots; they haveholdfasts that fasten to rocks orshells on the bottom of the sea.
C. Have children select one living or-ganism (trying to be sure that eachchild chooses a different one) andfind as much information as possible.Information can be discussed in oralreports.
D. To illustrate underwater life, chil-dren may work individually or in groupsconstructing a diorama. Cutouts ofvarious kinds could be hung by threadsat proper depths.
E. Make a mural showing different typesof ocean life (both animals and plants).
P. Investigate and report on aquaculture,the farming of the seas.
G. Have the class make a study of thedifferent zones in'which seashore
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XVIII The mineral wealth of the ocean isgreat, but unexploited.
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plants and animals of different kindsmay be found. Study life on a rockyshore, sandy beach, mud flat, wharf,or piling.
H. Not all the animals found in the seaare fishes or lower forms of animallife. Mammals are found in the sea,too. Study the sea otter, whale, dol-phin, seal, and sea lion. How arethese animals alike in their internalstructure? How are they different?
Minerals are found on the ocean floorin the form of nodules. A nodule isa lump. Nodules in the ocean areabout the size of potatoes and aremade of such minerals as manganese,cobalt, iron, nickel, and copper. Sofar, no inexpensive way has been foundto collect these nodules, but miner-alogists are trying to develop amethod.
Refer to chart to see the many uses ofthe ocean minerals to man.
A. Discuss the information above withthe class. Have some children findmore information and report to theclass.
1. Men who study the ocean7. Farming the ocean8: Rovers of the ocean11. Moisture in the air from the
ocean caused by the sun14. Underwater vessel
ACROSS:
2. Large mammal3. Project to examine the crust
of the earth4. Food of the sea5. Wealth of the ocean6. Underwater research vessel9. 'Uhderwater worker
10. Vessel used to recover lostbomb in the Mediterranean
12. Process of making fresh water13. Vast area of the ocean for
future use14. :le outer covering of the fish
4
ANSWERS:
OceanographersAquacultureCurrent
EvaporationSubmarine
Whale
MoholePlanktonMineralsDeepatarAquanaut
AlvinDesalinate
Continental ShelfScales
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BULLETIN BOARDS
1. Why do they float?
Display pictures of objects, Such as boats, swimmers, surf-boards, and rafts floating in water. You can also includelife jackets and life-saver rings. Let the children specu-late as to why these objects float and do not sink.
2. Show foods that we get from the sea. Use pictures of sea foodsfrom magazines and newspapers -- caviar, codfish cakes, tuna fish,etc.
3. Make a chart showing how man uses the wealth of the sea.
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FILMS
"Exploring the Ocean Floor" - 11 min., Churchill Films, Los Angeles,California
"Oceanography: The Science of the Sea" - 11 min., Film Association ofCalifornia
"What's Under the Ocean' - 14 min., Film Associates of California
"The Restless Sea" - The Bell Telephone Company
The Living Tide" - Dr. Roman Vishniae, Albert Einstein School of Medicine,New York City
"Secrets of the Underwater World" - a Walt Disney Production
"Science of the Sea" - Oceanographic Institute, Woods Hole, Mass.
FILMSTRIPS
"The Oceans" - 36 frames, McGraw-Hill Book Company
"Under the Sea" - 29 frames, Society for Visual Education
'Plant, Animal Life Under the Sea' - 32 frames, Society for Visual Education
"Plants and Strange Animals of the Sea" 65 frames, Jam Handy Organization
"How Fish get their Food" - 3-1-E3 Stoneham
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BIBLIOGRAPHY48
Barnard, J. Darrell - Science for Tomorrow's World. Grade 5, New York: TheMacmillan Company, 1966.
Bascom, W. - A Hole in the Bottom of the Sea,, Doubleday, 1961.
Beebe, William - Half Mile Down_._ Harcourt, 1934.
Bindle, Ruth About Undersea Exploration, New York: Random House, 1960.
Carrington, R. A. - A Biography of the Sea, Basic Books, Inc., 1960;
Carson, Rachel - The Sea Around Us, Oxford University, 1961.
Chapman, J. J. - Seaweeds and their Uses, Putnam, 1952.
Clark, Arthur - The Challenge of the Sea, New York: Holt, Rinehart andWinston, 1960.
Cousteau, J. - The Silent World._ Harper, 1953.
Cowen, R. D. - Frontiers of the Sea. Doubleday, 1961.
Daugherty, Charles - Searchers of the Sea, New York; Viking Press, 1961.
Epstein, Sam and Beryl - The First Book of the Ocean, New York: FranklinWatts, 1961.
Fischler, Abraham - Science_a Modern Approach, Grade 5, New York; HoltRinehart and Winston, 1966.
Navarra, John G. - Todav's Basic Science, New York: Harper, Row Publishers,1967.
Ramsey, William - Modern Earth Science. New York: Holt, Rinehart andWinston, 1965.
Sullivan, W. - Assault on the Unknown, McGraw Hill, 1961.
Zim, H. S. and H. H. Shoemaker Fishes. Golden Nature Guide, Golden Press,1956.
FORCES IN SPACE
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1 2attached to the helmet. A ship is
50..
OVERVIEW
Gravity and the natural laws of motion create problems in placing an ob-
ject in orbit or sending it into outet space. This unit is designed to show
these natural forces as they pertain to familiar objects in the child's envi-
ronment.
Motivating Activities:
1. Discuss a recent rocket launching.
2. Display news clippings of the latest developments and events occurringin astronautics.
3. Display a group of books about astronautics.
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Concepts
1. Gravity gives weight to all objects.
2. The force of gravity tends to hold all objects on earth.
3. Free falling objects fall at the same rate of speed.
4. Air offers resistance to objects moving through the atmosphere.
5. Gravity affects the distance an object can travel.
6. Gravitational attraction affects the path of a moving body.
7. For every action there is an equal reaction.
S. Energy of motion reacts against gravitational pull to create thrust.
9. The rocket engine works on the principle of Newton's third law.
10. A body at rest tends to stay at rest unless acted upon by someexternal force.
11. A body in motion tends to stay in motion and resists any effort tostop it.
12. A moving object tends to travel in a straight line.
13. Rockets must overcome the force of gravity to escape into outerspace.
14. Centrifugal force keeps the satellite in orbit. Whenever an objecttravels a curved path, a force is exerted on the object which is inthe direction away from the center of the curved orbit.
15. Speed and power/are necessary to place a satellite in orbit.
16. Added acceleration is necessary to escape the earth's force ofgravity when Shooting a space craft into outer space.
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Backg:-ouni:
-Gravity is a word which is used to describe or identify a phenomenonwhich no one has successfully explained in terms that can really be under-stood. What has actually happened is that man has given a label to aphenomenon which he cannot explain but can demonstrate. The understanding ofhow gravity acts upon objects on earth and in space is essential in many fieldsof science.
coNcAns EXPERIMENTS
I Gravity gives weight to allobjects
A. Materials: Spring scale and severalobjects
Itocedupel Weigh each object andread the weights indicated on theface of the scale. All objectshave weight because gravity pullsthem toward the center of the earth.
B. Materials: Soil, cup, bathroom scale,gallon pail
Procedure: Place pail on scale.Write the weight of the pail. Put4 cups of soil in the pail. How muchdoes the soil weigh? This is theamount gravity is pulling on the soil.Add more soil. Explain what gravityhas to do with the change of pressureon the scale.
II The force of gravity tends to hold A. Have children jump as high ss pos-objects on earth. sible. Discuss the fact that regard-
less of how hard they try, they cannotget very far off the surface.
B. Throw various types of objects intothe air. Observe that there is adifference in the height variousobjects can be thrown, but they allfall back to earth because ofgravity.
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III Free falling objects fall at the A. Materials: Pencil, book, eraser,
same rate of speed. ruler, coin
Procedure: Hold two of the aboveobjects at the same height and re-lease them at the same instant. Ob-
serve which object strikes theground first. Continue the experimentusing two different objects each timeuntil you have compared all the ob-jects and how they fall.
Explanation: All the objects willstrike the floor at the same instantfrom the same height. This isGalileo's Law of Free Falling Objects.There is, however, another part tothis law, concerning the effect ofthe resistance of air to free fallingobjects. If these objects had beendropped from a greater height, theywould not have landed at the sametime because of air resistance.
IV Air offers resistance to free fall- A. Materials: Sheet of papering objects moving through theeatth's atmosphere. Procedures: Drop a flat sheet of
paper from a height of 9 or 10 feet.Observe the path and rate of the flatsheet of paper. Crumple the paperinto a tight ball. Drop the crumpledpaper ball and note the rate of fall.
B. Materials: Large sheet of corrugatedcardboard
Procedure: Hold a large sheet ofcorrugated cardboard about waisthigh. Run as fast as possible andfeel the resistance of the air push-ing upon the cardboard. Repeat with-out the cardboard; note that it isnow easier to run fast.
V Gravity affects the distance an A. Materials: Softball, tape measureobject can travel.
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Procedure: Throw ball 3 times, firsteasily, then harder, then as hard asyou can. After each throw, measureand record the distance the ballcovered. Which throw caused the ballto cover the greatest distance? Make
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a list of factors (force, gravita-tion, air friction) which slowed andstopped the ball's movement.
VI Gravitational attraction affects A. Materials: A tennis ball and tablethe path of a moving body (satel-lite). Procedure: Roll the ball off the
edge of the table and mark the spotwhere it hits the floor. Do thisseveral times increasing the speedeach time.
Explanation: Gravity pulls on theball each time causing it to falltoward earth in an arc bending to-wurd the earth. With an increasein speed the ball moves fartherhorizontally while falling. For a .
ball to continue in an orbit aroundthe earth without hitting the ground,it mould have to travel at a speed of5 miles per second, or about 18,000M.P.H. This would be impossibleclose to the earth because air re-sistance would cause the ball to slowdown.
B. Materials: Book, magnet, steel ball,sheet of glass
Procedure: Place a thin book underone end of the sheet of glass so thatthe glass is tilted slightly. Slidea magnet under the other end of theglass.
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Allow the steel ball to roll down thesheet of glass. Observe the ballcarefully. How is the motion of theball affected by the magnet?
In this experiment the magneticattraction of the magnet works invery much the same way as the gravi-tational attraction of a planet.
You may wish to repeat this withstronger magnets ani various sizedsteel balls.
VII For every action there is an equal A. Materials: One balloonreaction.
Procedure: Blow up the balloon, closenezzle with fingers, then release it.
Explanation: The balloon moves rap-idly through the air in an erraticpattern. Its motion is due to theforce of the air leaving the nozzleof the balloon. This is explainedby Isaac Newton's Third Law of Motion,two bodies are involved in every forcefound in Nature, the body that exertsthe force and the body that receivesthe force. Force exists in pairs andnever alone.
In the case of the air-filled balloon,the air escaping from the balloon wasthe body that exerted the force andthe balloon received the force.The hot gases escaping through thenozzles of a rocket engine have thesame effect on the rocket body asthe air did on the balloon.
B. Materials: Masking tape, longballoons, wire, paper clips, balsastick ('" square x 12" long), 25feet of nylon sewing thread, 2 chairs
VIII Energy of motion reacts againstgravitational pull to createthrust.
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Procedure: Stretch the threadtightly. Make two hooks out ofpaper clips. Mount hooks at eachend of stick.
Blow up one balloon and hold tightlyso no air leaks out. Tape the balloonto the stick as shown.
Carefully slip the hooks over thethread. Let the balloon go and re-lease the air from it without shakingthe stick or thread.
Measure the distance the stick trav-eled. What was it?
Does it travel the same distance thesecond time?
C. Materials: Roller skates, basketball
Procedure: Haveskates and throw
As the ball goesrolls backward.
a child wear rollera basketball forward.
forward, the child
(Newton's Third Law of Motion)
D. Step off the rear of a small wagon.Note the direction the wagon moves.
-A. Materials: Dowel rod, string, 2 bal-
oons, 2 medicine droppers
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Procedure: Suspend a balanced dowelrod by means of a string tied at thecenter. Inflate two similar balloonsthrough medicine dropper tubes thathave been secured in the mouths ofthe balloons. Attach one balloon toeach end of the rod so that the med-icine droppers are horizontal andpointing in opposite directions.
/
B. To show how a narrow opening affectsthrust have children do this at home.Take a garden hose and turn on thewater. Place a finger over openingof the hose to make it smaller. No-tice the change in the force of water.
IX The rocket engine works on theprinciple of Newton's Third Law.
Illustration ora rocket motor:
i Propellant < Thrust
jEscapeozz le
CombustionEngine
Gas jet
Background: In the combustion chamber, the fuel-oxygen mixture is convertedinto gases which ignite at a high temperature, This combustioncauses the gas to expand, creating extremely high pressures withinthe chamber. A stream of high-speed gases is exhausted throughthe escape nozzle at the rear of the combustion chamber. Pressure'on the chamber wall opposite the nozzle pushes the rocket forward,The forward motion results from the forces crated interneIbt andnot from the exhaust gases pushing the outside air. The greaterthe internal push or thrust on the forward chamber wall.
A. Draw the diagram on the board anddiscuss its relation to Newton'sThird Law of Motion.
X A body at rest tends to stay at A. Materials: Glass, 3" x 5" card, coinrest unless acted upon by someexternal force. Procedure: Take a glass and place a
card over the open end. Place a coinon top of the card. Pull the cardsuddenly from under the coin.
Why does the coin fall into the.bottle?
Why do you have to pull the cardrapidly?
What could you say about the inertiaof the coin?
Explan ation: When the card is pulledrapidly from under the coin, the in-ertia of the coin at rest tends tocause it to remain at rest. Afterthe card is pulled from under it, theforce of gravity pulls the coin intothe bottle.
B. Materials: Glass jar or tin can,paper
Procedure: Set a glass tumbler or tincan on a sheet of paper in the centerof a table top. Hold one end of thepaper tightly in your hand and pullthe paper out from under it.
.11131
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XI A body in motion tends to stay in A. Materials: Thin board, newspapermotion and resists any effort tostop it. Procedure: Place a thin board under
some newspaper. The board shouldhang off the edge of the table.
71 - Board
Newspa r
Move your hand rapidly and hit theboard, attempting to break it withthe side of your fist. The boardshould break.
Repeat this experiment moving yourhand slowly. Why didn't the boardbreak?
Explanation: When you moved yourhand rapidly, it had considerableinertia. It was moving and tended tokeep moving. The board, however, wasat rest and tended to remain at rest.When your moving hand hit the board,its inertia of movement was such thatit overcame the resistance of theboard and broke it. When you movedYour hand slowly, it did not have asmuch inertia and as a result did notbreak the board.
B. Materials: Ball of foil, plastic con-tainer
Procedure: Put foil ball in a con-tainer. Lay the container on itsside on a table about 2 feet from theedge. Push the container along thetable quickly, stopping it at theedge of the table. The open end ofthe container should be in the direc-tion of the motion.
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JO
What happens to the ball? Why?(Effects of inertia and gravity)
Try using different amounts of forcein pushing the container. Givereasons for what happens. (Greaterforce produces greater forward mo-tion) .
XII A moving object tends to travel A. Materials: Foil, round shallow panin a straight line.
Procedures: Make a ball of the foil,and place it in a round shallow pan.Move the pan so that the ball goesround and round but stays in the pan.
Move the pan so that the ball goesaround faster and faster. Make themotion fast enough so that the ballleaves the pan. It should go out ina straight line until pulled down bygravity.
B. Materials: Tennis ball, string, tape
Procedure: Fasten one end of a threefoot length of string to a tennisball. Hold the other end of thestring in your hand and twirl the ballin a circular motion in front of you.Release the end of the string. Whathappens to the ball?
Explanation: When released, and be-fore gravity has an appreciable effect,the tennis ball will fly off in astraight path, in a direction tangentto the orbital path.
A satellite stays in an orbital patharound the earth because the gravita-tional pull of the earth bends itsstraight line path. The tension isin the string of the ball.
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XIII Rockets must overcome the force A. Materials: Kitchen scale, brick,of gravity to escape into outer spring scalespace
Procedure: Weigh the brick on thekitchen scale. It will probablyweigh about 5 pounds. Tie a stringaround the brick so that it will notslip off. Attach the spring scaleto the string. Watch the pointer.Lift the scale slowly and smoothlyuntil the brick is off the floor.
How much pull was shown on the springscale? Why did you need more than 5pounds to pick up this brick?
Explanation: The brick required forcegreater than its weight because ofits inertia, or tendency to remain atrest. When this inertia was over-come, the brick rose into the air.According to the second half of New-ton's First Law, the brick shouldrise indefinitely. It doesn't be-cause it is acted upon by the outsideforces of gravity and the friction-of the air.
Scientists have learned that theforce should be at least IA timesthe weight of the rocket.
B. Materials: Magnet, steel paper clip,and string
Procedure: Suspend a paper clip fromthe end of a length of string. Holda magnet in one hand and the sus-pended paper clip in the other hand.Keep moving the paper clip closer tothe magnet until it is attracted toit. Find the distance from the mag-net at which the paper clip isbarely attracted to the magnet.
Explanation: The paper clip may be'compared to a rocket which must es-cape the attractive force of theearth's gravity i.o "break away" intoouter space. One way for a rocket toescape the earth's gravitational pullis to attain a top speed of 25,000M.P.H. close to the earth's surface.
XIV Centrifugal force keeps thesatellite in orbit.
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Background: Whenever an objecttravels a curved path, a force isexerted on the object which is in thedirection away from the center of thecurved orbit.
A. Materials% Pail, water
Procedure: Fill a pail with water.Swing it around rapidly and observethat the water remains in the paileven when the pail is inverted.
B. Materials: Spool from thread, string,art gum eraser, or other light weightobject.
Procedure: Thread a 2-foot length ofstring through a spool. To one endtie a light weight object. .To theother end tie an object two or threetimes as heavy as the eraser. Holdingthe spool with the hole vertical, adjust the length of the cord from theeraser to the spool and the lengthfrom the spool to the other object sothat they are approximately equal.Move the hand holding the spool, sothat the gum eraser travels in a circleoverhead.
Explanation: The centrifugal forceexerted by the smaller swinging clayball will hold up the weight of thelarger clay ball.
If a satellite slows down, :Lt will bepulled toward the earth by a force ofgravity. This can be shown by slowingthe circular motion of the smallerobject.
XV Speed and power are necessary to L. Materials: Flannel board, flannel-place a satellite in orbit. back three-stage rocket cutouts, and
speed labels.
Procedure: Make cutouts according tofigure shown. These are comprised ofa three-stage rocket and the labelsindicating the speed to which eachstage accelerates.
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The following information can be pre-anted and discussed.
A satellite placed in orbit at an alti-tude of 300 miles must attain a speedof 18,000 M.P.H. To attain this speedmore power is needed than can pres-ently be provided by a single stage.This problem is solved by includingseveral stages. The first stage isthe largest and must produce the mostpower to overcome its own inertia andthat of two other stages, plus theforce of gravity and the air resist-ance closest to the earth.
The first stage attains a speed of4,000 M.P.H just as the fuel burnsout. With a running start, now of4,000 M.P.H., the second stage ignitesas the first stage drops off, andaccelerates to a speed of 10,000 M.P.H.With a running start of 10,000 M.P.H.,the third stage ignites as the secondstage drops off. At this time itattains a "horizontal" flightpath, fol-lowing the curvature of earth, and thesatellite or capsule is shot forwardinto orbit around the earth
f\ Satellite
18,000 M.P.H.
10,000 M.P.H.
4.000 M.P.H.
MI nik
Figures change in Demonstration 2
XVI Added acceleration is necessaryto escape the earth's force ofgravity when shooting a spacecraft into outer space.
64
A. Materialv: Flannel board, flannel-backed three -stage rocket cutouts,and speed labels
Procedures Refer to previous demon-stration. The speed label for thethird stage of rocket will be25,000 M.P.H., instead of 18,000 M.P.H.
Explanation: For a rocket to escapethe influence of the earth's gravity,it must accelerate to a speed of25,000 M.P.H., which is known as es-cape velocity. This is accomplishedby rocket staging.
The speed required for the rocket tocontinue climbing as it gets furtherout into space need not continue tobe 25,000 M.P.H., because the pullof the earth's gravity decreases asthe rocket gets further away from theearth.
When a rocket is fired toward the moonits third stage must accelerate to aspeed of 25,000 M,P.H., for it to es-cape the earth's force of gravity.After the fuel in the third stageburns up, the rocket keeps moving dueto inertia, but will slow down as itcontinues to travel toward the moon.At a distance of about 210,000 milesfrom the earth and about 30,000 milesfrom the surface of the moon, themoon's gravitational pull becomes thedominating attractive forL:a on therocket.
65
ADDITIONAL ACTIVITIES
1. Report on current happenings of space travel.
2. Collect articles and pictures from magazines and newspapers to make a spacescrapbook.
3. Construct scale models of United States rockets and satellites of wood,cardboard, papier-mache, or clay.
4. Draw a mural showing the development of apace travel, or space craft.
5. Make a list of things that depend on gravity. Check each one that youwould have to do on a space journey. How would you do these things?
6. Read and report on the first manned flights into space. You might be ableto answer these questions.
How long did the flight last?How were the men dressed?What experiments did the men have to do in space?What were their experiences with weightlessness?What did they discover about space?How was the capsule made to reenter the earth's atmosphere?
7. Find information about one or more of these scientists.
Robert GoddardColonel StappMontgolfier BrothersCaptain H. C. GrayAuguste Piccard
63
66
WORKSHEET
The Laws of Motion in Action
Here are four things that happened to Jim. Write why they happened.The main ideas you have learned about the laws of motion will help you explainwhy.
1. As Jim rode to school with his father, his father stoppedthe car suddenly at a red light. Jim was thrown forwarduntil his head almost hit the front window. Why was Jimthrown forward?
2. That day, Jim's father decided to put safety belts in the car.Why?
3. After school, Jim went sledding in the snow. The snow hadturned to ice. Jim found that once he gave his sled astarting push, it coasted a long way before it stopped.Why did Jim have to push his sled to start it moving?
What kept the sled moving after he pushed it?
Why did the sled finally stop moving?
4. At dinner, Jim's baby sister kept pushing things off thetable. She laughed with great glee as they dropped to thefloor. What natural force was amusing Jim"s baby sister?
'10
67
BULLETIN BOARD IDEAS
1. Display pictures and photographs on the bulletin board with.captions that motivate discussion. For example, under apicture depicting a rocket flying to the moon, the captionmight read, "Will you be one of the first passengers to themoon?"
2. Prepare a book-jacket bulletin board illustrating the booksabout space and space travel.
Prepare a bulletin board illustrating conditions necessaryfor man to live on the earth. The caption might read,"How can man meet these needs in space?"
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68
SPACE INFORMATION RESO1RCES
1. NASAEducations Publications Distribution CenterFADWashington, D. C. 20546
for "NASA FACTS" Living in Space - Volume III, No. 5Gemini Pictorial Volume IV, No. 1Orbiting Geophysical Observatory,
Volume II, No 3
2. Superintendent of SchoolsDept. of Education, San Diego County6401 Linda Vista RoadSan Diego, California 92111
Chart - How Big are Missiles?Picture - '"Astronaut's View of the Earth"
3. Nasa Electronics Research Center575 Technology SquareCambridge, Massachusetts 02139
FILMS
"How Man Travels Through Space" BW/color, 12 min. Cenco EducationalFilms
"Space Science: An Introduction", 14 min. EW and color - CoronetFilms
"Gravity and What it Does" (in Stoneham)
FILMSTRIPS
"Gravity" - Color, Young America Films
"Man in Space" - Color, Encyclopedia britannica Films
69
BIBLIOGRAPHY
Adler, Irving, Man-Made Moons, New York, John Day, 1957.
Asimov, Isaac, Satellites in Outer Space, New York, Random House, 1960.
Bendick, Jeanne, The First Book of Space Travel, New York, Franklin Watts,1963.
Blough, Glenn, Elementary School Science and How to Teach It
Brandwein, Paul F., Concepts in Science 5, New York: Harcourt, Brace& World, Inc., 1966.
Branley, Franklyn, Exploring by Astronaut, New York, Thomas Crowell, 1961.
Coombs, Charles, Lift-Off; The Story of Rocket Power, New York, Morrow,1963.
Craig, Gerald, Science for You, 5, Boston, Ginn, 1965.
Kambly, Paul E., Teaching Elementary School Science, New York, RonaldPress Co., 1963.
Ley, Willy, Rockets Missiles and Space Travel, New York, Viking Press,1961.
Newell, Homer E., Express to the Stars: Rockets in Action, New York,McGraw-Hill, 1961.
Parker, Bertha M., Rockets and Missiles, Satellites and Space Travel, NewYork, Harper and Row, 1963.
Schneider, Leo" Apace in Your Future, New York, Harcourt, 1961.
Schussler, Eileen and Raymond, Starbound: The Story of Rocketry, NewYork, Putnam, 1960.
Schwartz, Julius, The Earth is Your Spaceship, New York, McGraw-Hill,1963.
Verral, Charles, Robert Goddard: Father of the Space Age, EnglewoodCliffs, New Jersey, Prentice-Hall, 1963.
Smith, Herbert, q.4,ence.4,, New Jersey, Laidlaw Bros., 1966.
V
THE PROPERTIES OF HEAT
74
71
OVERVIEW
Heat, birdefinition, is a form of enery associated with the
rapid, random motion of molecules. Heat is transferred from one
substance to another by conduction, convection, or radiation and
usually produces a rise in temperature.
This unit will include the nature of heat, the effects of
heat, and how heat travels.
Motivational Activitu
1. Tracing all sources of heat back to the sun.
List as many different sources of heat as possible, example,friction, electricity, fires, atomic energy. Tell some ofthe things that heat from each of these sources does forthem. Then try to trace the heat back to the sun.
2. Display equipment to be used in the demonstrations andexperiments.
Concepts to be Developed
72
1. Heat 18 a form of energy - the energy of moving molecules.
2. As a substance gets warmer, its molecules move rapidly; as it
cools, less rapidly.
3. Solid substances generally expand when heated and contract whencooled.
4. When gases are heated, the molecules move farther apart and exertgreater pressure on the walls of the container.
5. Gases will contract when cooled.
6. Water is unique in that it expands just before it freezes.
7. The addition or removal of heat from a substance may cause itto change from one state into another.
8. Air carries heat.
9. Water carries heat.
10. Radiant energy carries heat.
11. Solids carry heat.
12. Dark colored materials absorb more heat than light coloredmaterials.
13. Clothing, blankets and home insulators are effective in pre-venting loss of heat because they contain trapped air whiCh isa poor heat conductor.
76
CONCEPTS EXPERIMENTS
I Heat is a form of energy, the A. Materials: nail, hammerenergy of moving molecules
II As a substance gets warmer itsmolecules move more rapidly; asit cools, less rapidly.
III Solid substances generally expandWhen heated and contract whencooled.
73
Procedure: Hit a nail several timeswith a hammer. Let the studentsfeel the nail. Compare withanother nail at room temperature.
B. Materials: sandpaper, board
Procedure: Rub sandpaper over aboard. Feel the warmth of theboard.
A. Explain this concept, after doingthe experiments for Concept I.
A. Materials: screw and screw eyeon two dowel stick handles.
Procedure: The screw should be justtoo large to go through the eye.When the screw eye is heated, itexpands, and the screw will gothrough it.
B. Materials: wire, two poles, weightsruler
Procedure: Suspend a wire from twopoles put a small weight on thewire. Measure the distance from thewire to the table top. Heat the wireand measure the distance.
IV When gases are heated, the mole- A. Materials: balloon, tube, heatcules move farther apart and exert sourcegreater pressure an the walls ofthe container. Procedure: Slip balloon over tube,
heat tube; air should expandballoon.
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V Gases will contract when cooled. A. Materials: ice cubes, container, fourballoons, light bulbs
Procedure: Blow the balloons up sothat they are the same size. Placeone by a heater; place one by aninfrared light or large light bulb;and place the third balloon in ice-cold water, over its surface. Leaveone balloon Lt room temperature.Observe results.
VI Water is unique in that it expands A. Materials: stiff plastic :refrigera-just before it freezes. for container with lid, cellophane
or masking tape
Procedure: Fill the plastic con-tainer to overflowing. Put lid oncarefully so that there is no air inthe container - only water. Tapethe lid on tightly. Put the con-tainer in the freezer. Leave itthere until it freezes. Containermight crack from expansion of ice.
VII The addition or removal of heat A. Materials: burner, ice cubes, threefrom a substance may cause it to containerschange from one state into another.
Water in three forms - discuss thethree states - show ice cubes meltinginto liquid state - water boilinginto steam
VIII Air carries heat. A. Materials: lamp chimney, candle, two(Convection) wooden sticks
Procedure: Light candle and setchimney over it on two blocks to raiseit above the table surface. Note thewarm air at the top of the chimney.Hold a smoking stick at the bottomof the chimney. This will show theair is moving into the bottom of thechimney and is traveling up to thetop. It is moving air that carriesthe heat. Hold a thermometer a footabove the chimney and note changes asthe air is warmed.
IS
75
B. Materials: thermometer, pole
Procedure: Fasten a thermometer tothe end of a pole and find the airtemperature near the coiling of yourroom. How does it compare with thetemperature near the floor?
C. Materials: ice cubes, container,thermometer
Procedure: Place some ice cubes ina container. Fill the container withwater. Every minute check the tem*perature of the water at the surfaceamd at the bottom. Be extremelycarerul not to stir the water. Re-cord your results and continue to re-cord temperatures for five minutes.After half an hour, check the sur-face and bottom results again.
IX Water carries heat. A. Materials: flask or Pyrex bottle,heat source, sand, thermometer
X Radiant energy carries heat.
Procedure: Fill a flask or Pyrexbaby bottle nearly full of water andheat it at the bottom. Hold a ther-mometer in the water at the top. It
soon shows the water is getting hot.The water at the bottom is travelingto the top, carrying the heat withit. Some grains of sand or piecesof sawdust placed in the bottle willshow how the currents are traveling.
A. Materials: candle, paraffin, a fire,a toaster, or any other object thatradiates heat.
Procedure: Light a candle and holda block of paraffin alongside it.The paraffin melts on the side ofthe flame. (The higher temperatureabove the candle is due to convectioncurrents, but the higher temperaturebeside it is caused by radiation.
B. Materials: mounted light bulb, threethermometers
76
Procedure: Place an unshielded elec-tric light bulb near the center of alarge table. Place three thermom-eters on the table so that each ther-mometer is one foot away from thebulb. Turn the bulb on. Wait fiveminutes. Check the temperature. Next,rearrange the thermometers at differ-ent distances from the light bulb.After five minutes, check the tempera-tures.
XI Solids carry heat A. Materials: silver spoon, plasticspoon
ZIT Dark colored materials absorbmore radiant heat than lightcolored materials.
8 0
Procedure: Place a silver spoon inhot water. Feel the spoon, Comparemetal spoon with plastic spoon. Whichis a better conductor?
B. Materials: metal bar, candle, fivethumb tacks
Procedure: Fasten the tacks to themetal bar with wax, close together ina row. Place one end of the bar inthe flame of a burner. Can you seehow the heat is traveling along thebar?
C. Materials: jar and lid
Procedure: Tighten the lid of a jara) it is difficult to loosen. Holdjar under the hot water. The metalwill expand more than the glass. Tryto loosen lid again. Result?
A. Materials: two thermometers, whitecloth, black cloth
Procedure: Put the two thermometersin sunlight. When they show the sametemperature, place a square of whitecloth over the bulb of one and a pieceof black cloth over the bulb of theother. The temperatures will change.
XXII Clothing, blankets and some home A.insulators are effective in pre-venting loss of heat, becausethey contain trapped air which isa poor heat conductor.
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Examine carefully home insulating orinsulated bags used for ice cream
B. Materials: three jars, 1 woul sock,1 cotton sock
Procedure: Fill three jars to thetop with hot water and cover themtightly. Wipe the outside of thejars dry, Pull a woolen sock aroundone jar, a cotton sock around thesecond jar, and leave the third jaras it is. Place all jars in a coolplace. After about a half hour, re-move the socks and feel the jars.Measure the water temperature with athermometer.
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FILMSTRIPS
"How Heat is Transferred" - 46 frames, McGraw -Hill Book Co.
"The Thermometer" - 44 frames, McGraw-Hill Book Co.
"How Heat is Transferred" - color, Young America Films
FILMS
"Heat and Its Behavior" - 11 min., Coronet Films
"Things Expand When Heated" - 10 min., McGraw-Hill Book Co.
"Transfer of Heat" - 11 mins., McGraw-Hill Co.
82
7J
BIBLIOGRAPHY
Blough, Glenn, Elementary School Science an4 How to Teach It, New York,Holt, Rinehart, Winston, 1964.
Jacobson, Willard, Light and Heat, New York, American Book Co., 1968.
Navarra, John G., Science Today for the Elementpry School Teacher, New York,Harper and Row, 1960.
Parker, Bertha Morris, Thermometers. Heat. and Cold Harper and Row, 1959.
Schneider, H., Science in Our World, Boston, D. C. Heath & Co., 1968.
83
CELLS OF THE BODY
84
80
81
OVERVIEW
Through studying cells, scientists are learning more and more
about life. This unit is designed to study the structure and function
of the individual cell, of the group of related cells called tissues,
and the group of related tissues called organs.
Motivational Ideas:
1. Place microscopes with slides of cells and tissue outto be independently observed.
2. Find pictures of cells, tissues, and organs to put onthe bulletin board.
3. . Display books with information about cells.
85
Concepts
82
1. According to the cell theory, all living things are made up ofcells.
2. The structure of the cell includes the nucleus, cell membrane,and cytoplasm.
3. Plant cells differ from animal cells in that they have a cellwall.
4. Plant cells have a cell membrane inside the cell wall.
5. Some of the materials in living cells are dissolved in water.
6. Some of the materials in living cells, such as fats and pro-teins, are not dissolved in water.
7. The cell membrane is living material that completely surroundsthe cell.
8. Substances that dissolve can enter and leave a cell that hasno opening through the cell membrane by osmosis.
9. Cells reproduce by means of cell division.
10. Groups of cells that work together are called tissues.
11. Groups of tissues that work together are called organs.
12. Organs that work together are called systems.
13. All the systems working together make up an organized livingsystem, or organism.
86
Background:
The cell theory has been accepted as the unit of life for only alittle more than 100 years. The cell theory says that all living thingsare made of one or more cells or of cells and their products. All cellscome from cells, and the activities of all living things are possible be-cause of the activities in cells.
CONCEPTS EXPERIMENTS
83
I According to the cell theory, all A. Find information about Theodorliving things are made up of cells. Schwann and Matthias Schleiden who
developed the cell theory.
II The structure of the cell includes A. Materials: microscope, glass slide,the nucleus, cell membrane, and iodine, water, clean medicine drop-cytoplasm. per, toothpick
Procedure: Put a drop of water onthe center of the glass slide.Gently scrape the inside of yourcheek with the side of the cleantoothpick. A whitish material willcollect on the toothpick. Thematerial is made up of cells fromyour cheek.
Mix this material in the drop ofwater. To see the cells more clear-ly under the microscope,. stain them.Add just one drop of iodine solutionto the drop of water on the elide.To make the solution, add one drop-perful of drugstore iodine to onecupful of water.
Place the slide under the lens of themicroscope. The shapes are cellsfrom the skin of your cheek. Canyou observe a dark spot in eachcell? It is the nucleus of thatcell, stained by the iodine solution.
B. Let the drop of water on the slidedry, and observe what happens to thecells. What do you think this re-sult means?
A
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C. Have children make a large drawingof what they see. Help them tolabel the parts of the cell.
III Plant cells differ from animal cells A. Materials: glass slide, cover slip,in that they have a cell wall as microscope, medicine dropper, onion,well as a cell membrane. iodine thinned with water, (1 part
iodine to 2 parts water)
Procedure: Place a drop of iodinein the center of a clean slide withthe medicine dropper. Gently pullthe skin off a piece of onion. Putthe onion skin in the drop ofiodine. Look at the onion skinfirst under the low power of yourmicroscope, then under the highpower.
The nucleus is probably the mostimportant part of the cell as itcontrols much of the activity thattakes place within the cell. Whena cell reproduces itself, or whena cell uses food or oxygen, thenucleus controls these activities.
Point out that a cell has threedimensions (length, breadth, andthickness).
IV Plant cells have a cell membrane A. Materials: onion skin, salt, waterinside the cell wall.
88
Procedure: Place a few drops ofweak salt water (27.) on a slidecontaining onion tissue. Tell thechildren to watch what happensunder the microscope.
They should see shrinkage of thecell contents. The membrane shrinksaway from the cell wall as waterleaves the cell. If purple Onion isused, this shows up very sharply.The purple color becomes more intenseinside the vacuoles, indicating lossof water by the cell.
85
Back ound:
A large part of the cell is water. However in the water are mineralsmade up of elements such as sodium, calcium, and potassium. Thereare sugars, fats, and proteins in the water, too. These are made upof carbon, hydrogen, oxygen, nitrogen, and other chemical elements.
V Some of the materials in living cells A. Materials: sugar, waterare dissolved in water.
Procedure: Mix a spoonful of sugarin the water. What happens to thesugar crystals? Why can't you seethem when the sugar is dissolved inwater?
Explanation: When sugar crystalsare mixed with water, they break upinto smaller bits called sugarmolecules. Sugar molecules are toosmall to see. The sugar seems todisappear when its molecules arescattered throughout the water. Youcannot even see them with a micro-scope.
VI Some of the materials in living cells, A. Materials: cooking oil, water, jarsuch as fats and proteins, are notdissolved in water. Procedure: Put a spoonful of cooking
oil in a jar of water, and you willsee that it does not mix with thewater. However, if you shake the jarhard for some time, some of the oilwill break up into smaller bits. Whenyou stop shaking it, they will eol-lect again at the top of the water.
B. Materials: egg white, toothpick
Procedure: Use a toothpick to exam-ine the white of an egg. Note howthick and sticky it is. Most of theegg white is protein and water. Theprotein is not dissolved in the water.In this way, egg white is somethinglike the contents of a cell.
VII The cell membrane is living mate-rial that completely surrounds thecell.
VIII Substances that dissolve can enterand leave a cell that has no open-ing through the cell membrane byosmosis.
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86
A. To make a model cell membrane:
Materials: a box of clear gelatin,starch, cologde, 3 or 4 small plasticbags (sandwich size), string, 3 smallpieces of clay, scissorst
Procedure: Boil one cup of water andstir in a package of gelatin. Afterthe gelatine is dissolved, add 4 cupcold water. Add a teaspoonful ofstarch, and another teaspoonful ofcologne.
Pour some of this mixture into aplastic bag. An amount the size ofa pingpong ball will'do. Add a smallround piece of clay about the size ofa pea. Tie the bag tightly with thestring so that it has the shape of aball. There should be as little airas possible in the bag. Cut away theunused part of the bag with scissors.
Make 3 or 4 of these cell models soyou can try several investigations.
Let the gelatin cool and harden over-night in the plastic bag.
A. Materials: A gelatin cell model,iodine solution, a bowl or jar, water
Procedure: Fill the jar about three-quarters full with warm water. Addjust enough iodine solution to turnthe water a light tan. Place thegelatin cell model in the jar.
1. Why did the gelatin turn blue andthen black?
Reason this way: Iodine turns starchblue and then black. The starch in-side the membrane slowly turned blue.The iodine reached the starch bygoing through the membrane which seemssolid enough.
IX Cells produce by means ofcell dividion.
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87
If starch had passed through the mem-brane, it would have met the iodinein the water outside the membrane.The water outside the membrane wouldhave turned blue.' Since the waterdid not turn blue, starch did notpass through the membrane.
B. Materials: cell model, dish, water
Procedure: Place another cell model .
in a dish of clear water. After a fewhours, smell the water in the dish.What has happened to the cologne inthe plastic bag?
A. Materials: packet of dry yeast powder, two lumps of sugar, two jars withscrew top lids, handkerchief, water
Procedure: Put water into one jaruntil it is about one-quarter full.Dissolve two lumps of sugar in thewater. Lightly cover a dime withyeast powder. Put this amount ofyeast into the jar of sugar water.Screw a cap loosely on the jar, sothat dust can't get in but gas canget out. There will be two millionyeast cells in the jar.
Leave the jar at room temperature forfour days.
More yeast cells form by cell division.How much more yeast is there now?Strain the yeast mixture through aclosely woven handkerchief or throughfilter paper into the second jar.This will filter out the yeast cells.Let them dry overnight. Compare themwith the amount of yeast you startedwith.
B. Materials: lump of clay
Procedure: Put the clay between your.
and.
hands and pull it apart. You willhave two lumps of clay representingtwo cells. Each of these can bepulled apart again to make more cells.
vu
C. Put diagram on board to show celldivision. Stress that the nucleusmust divide also.
--/FirstStage
Background:
All the cells that look alike are useful in theprotect, all bone cells support, and all muscle
Groups of similar cells are called tissues. Themake up your body may be divided into five kindstissues.
MiddleStage
p,(2/
LastStage
same way. All skin cellscells move.
billions of cells thatof cells that make your
1. Covering tissue - this tissue covers the surfaces inside andoutside your body.
2. Connective and supportive tissue - this tissue supports yourbody and holds your cells and other tissues together. Thecells of connective tissue spread among other cells and bindthem together. Bone cells build bone and teeth.
3. Muscle tissue - your muscleshave three kinds of muscles;food tube and blood vessels,your bones, which enable you
are formed from muscle cells. Youheart muscle, muscles of theand muscles that are attached toto move.
4. Nerve tissue - your brain nerves, and sense organs are made ofnerve tissue. Nerve tissue carries messages from one part ofthe body to another.
5. Blood tissue - two kinds of cells in blood are red cells andwhite cells. Red cells carry food and oxygen while white cellsfight disease.
X Groups of cells that work together A. Obtain prepared slides of the dif-are called tissues. ferent tissues (possible from the
high school). Examine to find thebasic parts of the individual cell.Compare the differences of the ap-pearance of the cells.
89
B. Have children look for pictures oftissues in books and magazines.
C. Examine a drop of blood under themicroscope.
D. You might write for samples of amicroviewer and slides of "Cellsof Your Body' #10.Address: National Teaching Aids, Inc.
120 Fulton AvenueGarden City Park,New York
Background:
Each organ is made of different kinds of tissues. The heart is mademostly of muscle tissue held together by connective tissue. It alsohas blood tissue and nerve tissue. All these tissues work togetherto form one organ.
XI Groups of tissues that work to- A. Discuss other organs in the body,gether are called organs. deciding on what tissue they contain.
B. Materials: Dead frog, knife
Procedure: Dissect a frog. Locateand describe the digestive organs,including the mouth, tongue, gullet,stomach, liver, gall bladder, pan-creas, and intestines.
XII Organs that work together are called A. Have children discuss the systems ofsystems, the human body: the nervous system,
respiratory system, digestive sys-tem, and the circulatory system.What major organs are related to eachone? Are there more than one kind oftissue in the system.
4
XIII All the systems working togethermake up an organized livingsystem, or organism.
94
90
B. Have the class divide into groupsto further study each system. They
could prepare reports, find pictures,and make charts and diagrams to pre-sent to the class.
A. Discuss this concept with the class.Ask for examples of organisms- -(people, rosebush, sparrow, etc.)
4
4
WORKSHEET
YEAST CELLS
91
Like all living things, yeasts need more than food and water to grow.They also need the right temperature in which to grow. Do yeasts growbest in a very cold temperature, in a very warm temperature, or in amedium, room temperature? Plan and carry out an investigation to find out.
1. Write how you would go about the investigation.
2. In the table below, write the results you observed.
Temperature
1
I
What happened to the yeast cells1
Very colc-.temperature
1
..,
Roomtemperature
Very warmtemperature
3. Study your results. What are your conclusions from them? Inwhich temperature do yeasts seem to grow best? (If you cannotreach any conclusions from this investigation, explain why youcannot.)
95
92
FORKSHEET
Fill in the chart:
Substance Dissolves in Water Does not dissolvein water
Sugar
Chalk dust
Salt
Pepper
Honey
Starch
Iodine
I. A cell membrane covers each cell. Everything that enters orleaves the cell must pass through this membrane.
A. Which substance would be more likely to pass through thecell membrane, a dissolved substance or one not dis-solved?
Explain your answer.
B. What substances that you tested would be most likely topass, through a cell membrane?
966
WORKSHEET
TISSUES AT WORK
93
Suppose you decide to sharpen a pencil. You get up from your seat. Youwalk to the pencil sharpener. You sharpen the pencil. Then you go back to
your seat. You sit down.
The tissues of your body must work together for you to be able to do evensuch a simple thing as sharpening a pencil.
Carry out the act of sharpening a pencil, thinking about what happens ateach step. Then write below one way in which each tissue helps you carryout the act.
1. Nerve tissue
2. Muscle tissue
3. Supporting tissue
4. Blood tissue
5. Covering tissue
BIBLIOGRAPHY
Barnard, J. Darrell, Science for Tomorrow's World, Grade 5, The Mac-millan Co., 1966.
Beeler, Nelson F., Experiments with Microscope
Brandmein, Paul F., Concepts in Science, Grade 5, Harcourt, Brace& World, Inc., 1966.
Burgd;of, Otto P., Adventure Book of Biology, Golden Press, Inc., 1962.
Darling, Lois and Louis, The Science of Life.
Hone, Elizabeth B., A Sourcebook for Elementary Science, Harcourt,Brace & World, 1964.
King, Fred and George Otto, Whnt is a Cell?
Schneider, Leo, You and Your Cells, Harcourt, Brace & World, 1964.
Wyler, Rose and Gerald Ames, WADI Book of Biology.
