Keep permanently in science notebook!
Designing a Scientific Investigation
Problem:
The question that you are trying to solve. The
problem is written as a question. Include the
independent and dependent variable in the problem.
Sample Problem: What is the rate at which different
rocks wear away?
Background
Information:
Research information collected about the topic.
The most recent references, such as science
magazines, are excellent sources. Become very
knowledgeable about your topic. Take notes and
summarize articles as you read.
Hypothesis:
An educated guess or explanation as to how the
problem might be solved. Base your hypothesis on
the background information you collected.
Sample Hypothesis: If some students take vitamin C
daily, then they will get fewer colds than the students
who do not take vitamin C.
(Write as If…then…statement)
Materials:
List of all the equipment needed to conduct the
investigation. Be specific when you list an item. Use
the International System of Units (SI).
Example: 250 ml beaker, Triple beam balance
Procedure:
The steps you will follow to test the hypothesis.
Describe all the steps involved in doing the
experiment. A controlled experiment is designed in two
parts.
Experimental Group
The test group. This
Control Group
group tests the
The untreated group.
independent variable.
The control group
Only one factor in the
provides basis for
experiment is changed.
comparison.
Procedure:
To test a hypothesis, scientists examine all factors that
can change during an experiment. Such factors are
called variables.
 Independent/Manipulated Variable: the one
variable that the experimenter chose to change.
 Dependent/Responding Variable: the items
that change as a result of the independent
variable.
Scientists test, or change only one variable at a time.
All other variables must be controlled, or kept
constant.
 Constants: the variables that need to be
recognized and not allowed to change.
EXAMPLE: If aspirin is added to cut flowers, then the
flowers with aspirin will stay fresh longer than the
flowers without aspirin.
Independent Variable: aspirin
Dependent Variable: freshness of flowers, time
flowers stay fresh
Constants: same type of flowers, same amount
of flowers, size of vase, amount of aspirin,
amount of water
Data/Results:
Data may be in the form of charts, graphs, pictures,
drawings, and descriptions or observations.
Quantitative data: data expressed in numbers
Qualitative data: descriptive data
This section tells what happened. What you observed
and measured.
Conclusion:
1. Tell the reader whether you reject or accept the
original hypothesis that you wrote.
2. Copy your hypothesis, word for word.
3. Describe what you did to “test” the hypothesis.
 Do not recopy the procedure here
 Name the tools that were used
4. Describe what you observed during the
experiment. Include numbers from the data
section.
5. Rewrite the hypothesis if necessary.