Problem SolvingRiddle

Steps Scientists Use to Solve Problems:

1. Make observations about the environment / State Problem or question

2. Gather information3. State a hypothesis4. Conduct Experiment5. Collect data6. State a conclusion7. Repeat many times

THE SCIENTIFIC METHOD!

The Scientific Method

Step 1: Objective (state the problem or question)

Example: Does exercise affect pulse rate?

Step 2: Gather information

• Study previous research in order to understand how the topic has already been explored

Step 3: State Your Hypothesis

• Educated testable guess

• Never a question!

• Example: Exercise will increase pulse rate

Step 4: Conduct the Experiment

• Experimental Group:

receives the treatment (ex.

Participants that exercise)

• Control Group:

receives NO treatment and is used as a comparison (ex. Participants that don’t exercise)

Two types of variables: (components that CHANGE during the experiment)

1) Independent Variable (X-axis)

This is what the researcher manipulates! (ex. Amount of exercise)

2) Dependent Variable (Y-axis)

“depends” on the original variable and is measured in the end (ex. Pulse rate)

Step 5: Collect Data

• In the form of a table, chart, or graph

Resting Group

Exercising Group

Trial 1

Trial 2

Step 6: Conclusion

• A few statements relating back to the hypothesis and discussing the outcome.

• ex. The data did/did not support our hypothesis. The average pulse rates of the participants that exercised were higher than those of the resting group. This could be due to…

In order for an experiment to be valid/reliable, it must have these

components… • Many trials• Large sample size• A control group

(most, not all!)• Other researchers are

able to repeat it!• Only test 1 variable at

a time (everything else remains constant!!)

Skittles Experiment

Problem: How many of each

color Skittle are in each bag?

Gather Information:

Read the back for info, feel and count through the bag, look at the colors on the bag

Hypothesis

There are…

___ red Skittles

___ blue Skittles…

What was missing from this experiment???

• Sample size too small! / not enough trials

• Independent variable missing

• No control group (more of a ‘study’ than an experiment)

• Not enough info to make an educated guess

Any Hypothesis is Valuable!

• Why?

• Because even if it is NOT supported by the data, it can still lead to further investigation!!

When does a hypothesis become a theory??

• When it becomes a well accepted body of knowledge that has been supported by many experiments over time!

Graphs

Today I want you to help me make a graph.

I want to make a graph that shows the change in temperature throughout the day yesterday.What kind of graphs could we make to show this?

Line Graph!!

Bar Graph vs Line Graph

• What is the difference between a bar graph

and a line graph?

Line Graph•A line graph is a graph

used to show change over time!!

Time can be measure in…Seconds - Minutes - Hours – Days - Weeks - Months – Years - Decades -

Centuries - etc.

When to use a line graph? Would we use a line graph

in the following situations:•To show how many people like pizza in this class? NO

•To show how many people live in Bellmore? NO

•To show how much it rained each month this year? YES- because months and years deal with time.

YOU TELL ME….

What color is the y-axis?

What color is the x-axis?

Y

X

D ependent

R esponding

Y M anipulated

I ndependent

X

Line Graphs

• Show a comparison between 2 variables

• Show how the independent v. affects the dependent v.

U.S. Corn in Acres

55

60

65

70

75

80

85

Years

Acre

s o

f co

rn (

in m

illi

on

s)

Bar Graphs

• Are descriptive and compare amounts or categories

• Are best for comparisons

Bar GraphPresents “categorical data”, data that fits into categoriesEx. Type of donut

HistogramPresents “continuous data”, the numbers can take on any value in a certain range Ex. weights of individuals