Designing an
Experiment
Flow Chart of Scientific
Method- brainpop
What is an experiment?
It is an organized plan to test a
hypothesis.
An experiment follows a definite
plan.
It documents data
gathered.
It attempts to answer a
question(s).
Components of an Experiment
 1. The Question, Purpose, or
Reason for the experiment
 2. Research – find background info
to help with the experiment.
 3. The HYPOTHESIS
Components of an Experiment
 4. The Experimental Phase
Materials
Procedures
Components of an Experiment
 5. Results
 6. Conclusions
I. Posing a QUESTION
1. Design the experiment to
solve the question or problem.
2. Narrow down the question —
be specific about what you
want to find out.
3. Investigate one “?” at a time.
III. Develop a HYPOTHESIS
A hypothesis is based on observations
and previous knowledge or experience
1. It MUST be testable.
2. It is a POSSIBLE ANSWER to
your question.
3. A hypothesis takes the form of
an If… then… Statement.
Variables
 A variable is any factor that can change
in an experiment.
Variables must be identified in order to
test the hypothesis.
Identifying the Variables
Types of variables:
1. Manipulated Variable
a. Also known as the independent variable
b. The factor you will be purposely.
changing and testing.
c. is shown on the
horizontal axis of
a graph.
Identifying the Variables
2. Responding Variable
a. also known as dependent
variable
b. The variable you predict will
change as a result of the
manipulated variable.
c. Is shown on the vertical axis of
a graph
If… then… statements
 If (manipulated or independent variable) ,
then (dependent variable).
• A hypothesis is written as an If… then…
statement.
• These statements must be written in correct
grammatical form.
IV. The Experiment
 Materials – make a list of all
the materials needed to
conduct your experiment.
III. The Experiment
 Procedures (How to do the
experiment)
The Procedures
Includes a brief description of the
experiment.
Identifies a plan to collect data and the
variables
Listed in numbered step-by-step
description of how to conduct
the experiment.
(Procedures – cont’d)
Prepare a data table
Record - How the manipulated
variable effects the responding
variable
A “Controlled” Experiment
1. All conditions (variables)
are kept the same except for
the manipulated variable.
2. A “control” is used as a
comparison in the
experiment.
(A standard against which
to measure results.)
V. Gathering & Interpreting
Data
Gather your data during the
experiment in a data table and log.
V. Gathering & Interpreting
Data
Make a graph from the data
table
V. Gathering & Interpreting
Data
Explain the data:
Look for comparisons, trends,
patterns
Make inferences from data and
compare them with what you
already know
Ask & answer: how, what, why.
VI. Conclusion -
Your
reflections on what happened in the
experiment.
Compare data and graph with
your hypothesis and decide
whether the
hypothesis is
true or false.
VI. Conclusion
Reflect upon & discuss your how,
what, why
answers.
VI. Conclusion
 Raise new questions and
redesign a new experiment.
VI. Conclusion
 Make a statements that summarize
what “you” have learned from the
experiment.
Science is…