Given the following research topic, answer the questions below: Are there differences in third grade reading scores between children who attended independent preschool, district provided preschool, or no outside preschool?

a. What is the dependent variable(s)?

b. What is the independent variable? Identify any levels of the variable.

c. Why is this an example of ex post facto research and not correlational?

d. Why is this an example of ex post facto research and not experimental?

e. What extraneous variables might there be in this study? Identify and describe at least three.

f. Select one of the potential extraneous variables and suggest one way to control that variable.