The Scientific Method
The Scientific MethodThe steps taken in a specific order to get an answer to
a posed problem.
Steps of the Scientific Method
1. Problem
2. Hypothesis
3. Experiment
4. Results
5. Conclusion
Step 1: Identify the Problem
• Using observations, identify a problem you would like
to solve.
o Observations are done with your five senses to gather
information.
o Ask questions that lead to a problem.
Step 1: Identify the Problem
• Two types of observations:
– Quantitative observations—deal with numbers
• Ex. 100 degrees outside
– Qualitative observations—deal with a description
• Ex. Its hot outside.
Step 2: Develop a Hypothesis
• A hypothesis is a possible answer to a scientific question.
oNot a fact (prediction)
oBased on observations and knowledge
oMust be testable
Step 2: Develop a Hypothesis
• Write your hypothesis using your variables (what is changing)
• Hypothesis Format:
– “If (what is changing on purpose) then (what is changing due
to what you already changed) because…
• “If ______________________then ____________
________________ because…
• Example:
Step 2: Develop a Hypothesis
A scientist wants to know if water boils at a higher temperature when salt is added.
Here is their experiment:
One Quart of
Boiling Water
with
One Quart of
Boiling Water
with
One Quart of
Boiling Water
with
NO SALT
TWO
TABLESPOONS
OF SALT
FOUR
TABLESPOONS
OF SALT
Question: How does the amount of salt affect the temperature where water
boils?
Hypothesis: If there is more/less (circle one) salt then water will boil at a
higher/lower (circle one) temperature because _____________________________.
• Example:
Step 2: Develop a Hypothesis
Maria is from planet DontKnowALot. She is doing an experiment. She has three people in
her experiment.
Person 1 will drink only
water.
Person 2 will drink only
juice.
Person 3 will drink only
Coca Cola.
Maria will measure the amount of weight that each person gains after a month.
Question: How does the type of liquid affect how much weight a person gains?
Hypothesis: If _________________________________________,
then _______________________________________________
because _____________________________________________.
Independent Practice:
• Complete Figure 2 on developing a
hypothesis.
The Scientific Method
Step 3: Test the Hypothesis
Testing the hypothesis is simply conducting the
experiment (materials and procedure.
• Procedure
• Materials:
• Step by step instructions
• A list of all the things
• Identifies the variables
you need
used in the experiment
Step 3: Test the Hypothesis
Variables- factors that can change in an experiment,
must be the same.
Variables Video
Step 3: Test the Hypothesis
Independent Variable- the one variable that is
purposely changed to test a hypothesis
Step 3: Test the Hypothesis
Dependent Variable-the factor that may change in
response to the independent variable
Step 3: Test the Hypothesis
Controlled Experiment-an experiment in which only
one variable is changed at a time
Guided Practice:
Which people in the experiment are in the control
group?
Guided Practice:
What are the independent and dependent variables?
Explain.
Guided Practice:
What should Mr. Krabb’s conclusion be?
Why is Group B reporting feeling better?
Independent Practice:
• Complete worksheet on conducting
an experiment.
The Scientific Method
Step 4: Results
Collecting data is writing down the results of the
experiment.
Data should be recorded in a table.
Step 4: Results
Data- are the facts, figures, and other evidence gathered
through qualitative and quantitative observations.
Step 4: Parts of a Graph
Guided Practice:
• With your partner, use the data below to create a
graph.
Height of the Plant by Day with
Plant by Day with Fertilizer
Day
Height (cm)
1
2
3
4
15
18
23
24
Guided Practice: Graphing
The Scientific Method
Step 5: Conclusion
A conclusion is a summary of what you have learned
from an experiment.
Ask yourself: Does my data support my hypothesis?
Step 5: Conclusion
Communicating is the sharing of ideas and results with
others through speaking and writing.
Before an experiment is published other scientists must
test it for accuracy.
Step 5: Conclusion
Scientific theory- a well-tested and widely accepted
explanation of observations and experimental results.
Step 5: Conclusion
Scientific law-describe observed patterns in nature
without trying to explain those patterns.