Independent Variable - The hair colour of our participants.

Dependant Variable - The participants thinking skills based on the test we gave them.

Controlled variables - The sex and age of the 40 people we had complete our test. 

- The 40 people who completed our test, filled it out around the same time of day.

- No one who completed our test knew what our science fair project was about, therefore they would give us accurate results.

- The test we used remained the same throughout our experiment

- We used an equal amount of blonde’s and brunette’s, children and adults, male’s and female’s to fill out our test.