1. Identifying, Manipulating and Controlling Variables
Paper Wicks
Identifying, Manipulating and Controlling Variables

2. Paper Wicks
At the heart of the scientific process is the effort to explore
the influence of variables upon a phenomenon. This is done
by (1) identifying possible factors that might influence the
phenomenon, then by (2) attempting to hold all factors constant
except one, which is systematically changed, then by (3)
concluding that any changes in the overall phenomenon must be
result of changes in the manipulated variable.
It is important to recognize that just because a variable can be
identified it does not follow that it must be influential. Assigning
importance to obvious but not influential variables is common
for non-skeptical thinkers and a typical component of scams.

3. Paper Wicks
In this activity we will explore the variables that might influence
the way construction paper soaks up water.
A construction paper strip when suspended into water will work
as a wick and draw water up the length of the strip. Through
manipulating the variables we will determine which ones will
influence the “wickability” of the strip.

4. Materials Needed A shallow container.
Several different colored sheets of construction paper.
7 or 8 plastic soda straws.
4 pieces of modeling clay
2 straight pins.
Cellophane tape.
Scissors
Writing materials.

5. Step 1 Use a straight pin to join 2 straws together.
Stick the long end of the straws into the clay so the pieces will stand. These will serve as legs.

6. Step 2
Join three straws together by pinching the end of one straw and sliding it into the opening of another.
Place this cross piece over the two sets of legs.
The dish must fit between the legs.

7. Step 3
Add water to the dish until it is about 1/2 full.

8. Step 4
Cut strips of construction paper that are about 3 cm wide by 12 cm long.
Add a piece of tape to one end.
Tape the strip of paper to the cross piece.

9. Step 4, continued Return the cross piece to the legs.
Your strip of paper should now be able to hang down into the dish below.

10. Step 5
Examine the construction paper. What variables might be involved in the phenomenon (construction paper acting as a wick)?
Make a list of them.

11. Step 6 Does your list contain… color of the paper?
width of the paper strip?
temperature of the water?
others?

12. Step 7
Try this experiment that allows you to test the influence of color on the rate at which the water will wick up the paper strips.
What variables are being controlled?
What do you expect will happen in this test?
To listen to while you set up the
experiment.

13. Step 7, continued
This picture shows three different strips after one minute.
Does there appear to be a difference?
What do you think will happen with time?

14. Step 8 Here’s another experiment. What variable is being tested?
Which one(s) are being controlled?
What do you predict will happen here?

15. Step 9
Design and conduct two experiments with paper wicks. Include the following:
variable to be tested
variables to be controlled
Report the results of your experiments to the class website.

16. Relax a little while. This activity is over.