The document discusses problem statements for scientific experiments. It explains that a good problem statement is a single question that identifies the independent variable being changed and dependent variable being measured. It provides examples of good problem statements that test the effect of one independent variable on one dependent variable. Poor problem statements are too broad or can be answered with yes/no. The document encourages choosing a problem statement that can be experimentally tested.

1. 1
Scientific Method
Problem Statement

2. 2
What is a Problem Statement?
 The question that you select for
your investigation – the basis of
your experiment.
 The research and experiment
you will be conducting center
around finding an answer to the
question or problem statement.

3. 5
A Good Problem Statement
(or Purpose)
 The problem statement only needs to be
one sentence long.
 The problem statement is always in the
form of a question.
 Should be open-ended (not answered by
yes or no)
 A problem statement includes what is
changed (independent variable) and what
is measured (dependent variable).

4. 6
A Good Problem Statement
How does light affect the reproduction
of bread mold on white bread?
Note the question is about:
 one life process
 one type of mold
 one type of bread
 one factor that affects it growth
(reproduction)
(bread mold)
(white bread)
(light)

5. 7
A Poor Problem Statement
How does light affect molds?
Note the question would have to test:
 all the life processes of mold
 all types of mold
 all types of growth mediums
 one factor that affects its growth (light)

6. 8
Choose a problem that can be
solved experimentally
Look at each question below and evaluate. Is it an example
of a good or poor problem statement? Explain why.
What is mold?
 Poor problem statement because it can be answered by
finding the definition of the word mold in the dictionary.
Will a green plant stay green if grown in the dark?
 Poor problem statement because it can be answered by
a yes or no.
How does temperature affect the growth rate of bread mold
on white bread?
 Good problem statement because it can be answered
by experimentation.

7. 13
Now, pick 1 bad problem statement and re-write
it to make it better. Use the following
templates or your own:
 What is the effect of (a) on (b)?
 How does (a) affect (b)?
 In what way does (b) depend on (a)?
 Which (a) will (b)?
(a) - is the independent variable
(b) - is the dependent variable