Date post: | 31-Dec-2015 |
Category: |
Documents |
Upload: | jayme-whitley |
View: | 13 times |
Download: | 0 times |
ENGINEERING DESIGN IN THE SCIENCE CLASSROOM
CHRISTINE SCHNITTKAUNIVERSITY OF KENTUCKY
LARRY G. R ICHARDSUNIVERSITY OF V IRGINIA
SUSAN K . DONOHUETHE COLLEGE OF NEW JERSEY
Engineering Teaching Kits
Engineering Teaching Kits2
Save the Penguins
Save the Penguins ETK4
Targeted Demonstrations
The CansThe TraysThe
SpoonsThe HouseThe Mylar
5
Alternative Conceptions about HT
•Cold is a substance that moves•Heat is a substance that rises•Heat is a substance like a fluid, made of particles•Larger ice cubes are colder than small ones•Metal is cold, plastic and wood are warm•Aluminum foil traps “coldness”; metals hold “cold”•Sweaters warm things
(Albert, 1978; Clough & Driver, 1985; Erickson, 1979; Erickson, 1980)
6
Videos about Penguins
Penguin in a PicklePenguin PopulationsPenguins are Melting
Penguin in a Pickle
Penguin Populations
Penguins are Melting
Penguins in South Africa
12
13
The Engineering Design Process
Identify the Need Define the ProblemBrainstorm IdeasConduct ResearchDevelop Design
Revise DesignTest Design
As Energy Demands Grow…
… more electricity or fuel is used.… burned fuels create carbon dioxide.… power plants usually burn coal- which
produces carbon dioxide too… carbon dioxide is implicated in global
warming… global warming is not our friend.
So, How Can We Save the
Penguins?
Save the Penguins ETK17
18
Engineering Design Process
Test Materials, Design, and Build!
Test materials if you are not sure which ones to use.
Think about conduction with the floorThink about convection (hot air entering the
house)Think about radiation from ALL sides (even
the bottom)Your constraints are space and time.Try to stay under a $200 budget! Extra
materials are available for purchase (trade).
Results: Design Iterations20
4.7 g remaining
6.3 g remaining
5.5 g remaining
7.0 g remaining
3.1 g remaining
5.7 g remaining
3.9 g remaining
6.0 g remaining
Heat Transfer Evaluation - Pilot Study
21
0
2
4
6
8
10
12
Eighth graders Other universitystudents
Engineering students
Mea
n s
core
Heat Transfer Evaluation
1. You pick up a can of soda off of the countertop. The countertop underneath the can feels colder than the rest of the counter. Which explanation do you think is the best?
a. The cold has been transferred from the soda to the
counter.b. There is no heat energy left in the counter beneath
the can.c. Some heat has been transferred from the counter to
the soda.d. The heat beneath the can moves away into other
parts of the countertop.
22
Heat Transfer Evaluation
1. You pick up a can of soda off of the countertop. The countertop underneath the can feels colder than the rest of the counter. Which explanation do you think is the best?
a. The cold has been transferred from the soda to the counter.
b. There is no heat energy left in the counter beneath the can.
c. Some heat has been transferred from the counter to the soda.
d. The heat beneath the can moves away into other parts of the countertop.
23
Heat Transfer Evaluation
2. After cooking an egg in boiling water, you cool the egg by putting it into a bowl of cold water. Which of the following explains the egg’s cooling process?
a. Temperature is transferred from the egg to the
water.b. Cold moves from the water into the egg.c. Energy is transferred from the water to the egg. d. Energy is transferred from the egg to the water.
24
Heat Transfer Evaluation
2. After cooking an egg in boiling water, you cool the egg by putting it into a bowl of cold water. Which of the following explains the egg’s cooling process?
a. Temperature is transferred from the egg to the water.
b. Cold moves from the water into the egg.c. Energy is transferred from the water to the egg. d. Energy is transferred from the egg to the water.
25
Heat Transfer Evaluation
3. Why do we wear sweaters in cold weather?
a. To keep cold out.b. To generate heat.c. To reduce heat loss.d. All of the above.
26
Heat Transfer Evaluation
3. Why do we wear sweaters in cold weather?
a. To keep cold out.b. To generate heat.c. To reduce heat loss.d. All of the above.
27
Heat Transfer Evaluation
4. Amy wraps her dolls in blankets but can’t understand why they don’t warm up. Why don’t they warm up?
a. The blankets she uses are probably poor insulators.b. The blankets she uses are probably poor conductors.c. The dolls are made of materials which don’t hold heat
well.d. None of the above.
28
Heat Transfer Evaluation
4. Amy wraps her dolls in blankets but can’t understand why they don’t warm up. Why don’t they warm up?
a. The blankets she uses are probably poor insulators.b. The blankets she uses are probably poor conductors.c. The dolls are made of materials which don’t hold heat
well.d. None of the above.
29
Heat Transfer Evaluation
5. As water in a freezer turns into ice,
a. the water absorbs energy from the air in the freezer.b. the water absorbs the coldness from the air in the
freezer.c. the freezer air absorbs heat from the water.d. the water neither absorbs nor releases energy
30
Heat Transfer Evaluation
5. As water in a freezer turns into ice,
a. the water absorbs energy from the air in the freezer.b. the water absorbs the coldness from the air in the
freezer.c. the freezer air absorbs heat from the water.d. the water neither absorbs nor releases energy
31
Heat Transfer Evaluation
6. On a warm sunny day, you will feel cooler wearing light colored clothes because they
a. reflect more radiation.b. prevent sweating.c. are not as heavy as dark clothes.d. let more air in.
32
Heat Transfer Evaluation
6. On a warm sunny day, you will feel cooler wearing light colored clothes because they
a. reflect more radiation.b. prevent sweating.c. are not as heavy as dark clothes.d. let more air in.
33
Heat Transfer Evaluation
7. If you put a metal spoon and a wooden spoon into a pot of boiling water, one will become too hot to touch. Why?
a. Metals conduct heat better than wood.b. Wood conducts heat better than metals.c. Metals pull in heat because heat is attracted to
metals.d. Wood isn’t as strong as metals.
34
Heat Transfer Evaluation
7. If you put a metal spoon and a wooden spoon into a pot of boiling water, one will become too hot to touch. Why?
a. Metals conduct heat better than wood.b. Wood conducts heat better than metals.c. Metals pull in heat because heat is attracted to
metals.d. Wood isn’t as strong as metals.
35
Heat Transfer Evaluation
8. On a hot day, the upstairs rooms in a house are usually hotter than the downstairs rooms. Why?
a. Cool air is less dense than hot air.b. Warm air rises and cool air sinks.c. The upstairs rooms are closer to the sun.d. Heat rises.
36
Heat Transfer Evaluation
8. On a hot day, the upstairs rooms in a house are usually hotter than the downstairs rooms. Why?
a. Cool air is less dense than hot air.b. Warm air rises and cool air sinks.c. The upstairs rooms are closer to the sun.d. Heat rises.
37
Heat Transfer Evaluation
9. You have a can of soda in your lunchbox that you want to keep cold. Which material will work best to keep it cold?
a. Aluminum foil wrapped around the soda because metals transfer heat energy easily.
b. A paper towel wrapped around the soda because paper soaks up the moisture.
c. Wax paper wrapped around the soda because wax paper traps the moisture.
d. Your wool sweater wrapped around the soda because wool traps air.
38
Heat Transfer Evaluation
9. You have a can of soda in your lunchbox that you want to keep cold. Which material will work best to keep it cold?
a. Aluminum foil wrapped around the soda because metals transfer heat energy easily.
b. A paper towel wrapped around the soda because paper soaks up the moisture.
c. Wax paper wrapped around the soda because wax paper traps the moisture.
d. Your wool sweater wrapped around the soda because wool traps air.
39
Heat Transfer Evaluation
10. When you hold a metal coat hanger in a camp fire to roast a marshmallow, the coat hanger might get too hot to hold. Why might the coat hanger get too hot?
a. The heat radiates along the coat hanger.b. The heat builds up near the flame until it can’t hold it
anymore and then moves along the coat hanger.c. Metal atoms vibrate with more energy when they get hot,
and they collide with atoms near them, which makes the neighboring atoms vibrate too.
d. Since metals melt in fire, they react very strongly to fire and get hot easily.
40
Heat Transfer Evaluation
10. When you hold a metal coat hanger in a camp fire to roast a marshmallow, the coat hanger might get too hot to hold. Why might the coat hanger get too hot?
a. The heat radiates along the coat hanger.b. The heat builds up near the flame until it can’t hold it
anymore and then moves along the coat hanger.c. Metal atoms vibrate with more energy when they get hot,
and they collide with atoms near them, which makes the neighboring atoms vibrate too.
d. Since metals melt in fire, they react very strongly to fire and get hot easily.
41
Heat Transfer Evaluation
11. An aluminum plate and a plastic plate have been in the freezer all night long. When you remove them the next morning,
a. The plates have the same temperature.b. The plastic plate has a higher temperature.c. The plastic plate has a lower temperature.d. The aluminum plate has a lower temperature.
42
Heat Transfer Evaluation
11. An aluminum plate and a plastic plate have been in the freezer all night long. When you remove them the next morning,
a. The plates have the same temperature.b. The plastic plate has a higher temperature.c. The plastic plate has a lower temperature.d. The aluminum plate has a lower temperature.
43
Heat Transfer Evaluation
12. When placed in direct sunlight, which object will absorb the most radiation?
a. a white sweaterb. a snowballc. some aluminum foild. a black sweater
44
Heat Transfer Evaluation
12. When placed in direct sunlight, which object will absorb the most radiation?
a. a white sweaterb. a snowballc. some aluminum foild. a black sweater
45
Methods
ETK+DSave the
Penguins with five targeted demos
n=23( 12M, 11F)n=11 pre-
interviewsHTE and ATES
pretest/posttestn=10 exit
interviews
46
Control
• Typical instruction: labs, lectures, demos
• n=27 (17M, 10F)
• n=10 pre-interviews
• HTE and ATES pretest/posttest
• n=10 exit interviews
ETK
• Save the Penguins without five targeted demos
• n=21 (9M, 12F)
• n=8 pre- interviews
• HTE and ATES pretest/posttest
• n=10 exit interviews
Equivalent scores on pretests, and 7th grade math and reading VA SOLs
Results: Heat Transfer- pre
Pretest scores on Heat Transfer Evaluation
ETK: M=4.33Control: M=4.63ETK+D: M=4.09F(2,68) = .601p = .551
47
CONTROL
ETK+D
ETK
Results: Heat Transfer- pre
Cold transfersMetals trap coldMetals are colder than plasticsLight colors reflect radiation/ dark colors
absorbMetals are conductorsHeat risesHot air risesInsulators generate heatSweaters reduce heat loss
48
Results: Heat Transfer- after49
ETK: M=6.43Control:
M=7.19ETK+D:
M=8.22
Results: Heat Transfer- after50
Pre-Posttest Gains on Heat Transfer Evaluation
Repeated measures ANOVA F(2,68) = 6.659 p = .002
ANCOVA F(2,67) = 6.549 p = .003
Results: Heat Transfer- after51
ANOVA comparisons
ETK+D to Control, p = .005
ETK+D to ETK, p = .002
Control to ETK, p = .448
Results: Eng Attitudes- pre52
CONTROL
ETK+D
ETK
• Pretest scores on Attitudes toward Engineering Survey
• ETK: M=3.35
• Control: M=3.52
• ETK+D: M=3.64
• F(2,68) = 2.271
• p = .111
• Cronbach’s α = .76
Results: Eng Attitudes- pre53
Researcher: Do you have any idea what an engineer’s job would be?
Kate (ETK Class): Like driving a train?Researcher: What kinds of people do you think
grow up to be engineers?Kate: Ones who like driving trains.
Researcher: Do you have any idea, what an engineer might do for a living? What their job might be?
Woody (Control Class): Fix cars.Researcher: Any other things engineers might do?Woody: Fix automobiles. Fix planes. Fix something
mechanical.
Results: Eng Attitudes- after54
• ETK: M=3.57• Control:
M=3.61• ETK+D:
M=3.90
Results: Eng Attitudes- after55
• Pre- Posttest gains on Attitudes toward Engineering
• ETK: M=3.57 t(20) = 3.739, p = .001
• Control: M=3.61 t(26)=1.347, p = .190
• ETK+D: M=3.90 t(22)=2.659, p = .014
Control males:t(16) = 0.296, p = .771
Gender Effect ? - Eng Attitudes56
ETK males: t(8) = 2.290, p=.051
ETK+D males:t(11) = 1.147, p = .276
Control females:t(9) = 1.904, p = .089
ETK females: t(11) = 2.939, p =.013
ETK+D females:t(10) = 2.905, p = .016
Conclusions/ Implications
•Engineering design can promote conceptual change as well as typical instruction
•ETK+D is better than typical or ETK alone• Students’ alternative conceptions should be
addressed•Middle school teacher can implement
engineering design with some basic training• Engineering design activities can promote
positive attitudes toward engineering
57