During this activity, students will be able to understand why they have to control variables and to repeat their measurement and it leads discussion for understandings about inquiry as well as abilities to do inquiry.
Students are asked to predict the number of head/tail of a penny when tossing it 10 times and they test their predictions. Then, students repeat the same procedure by tossing two pennies at once.
The reflective questions include “Should the same person flip the coin?” “Did anybody pay attention to the head on the top and the tail on the bottom when you flipped it? Did you use always the same way?” in order to discuss the importance of controlling variables. It is also discussed how much difference between data and the theoretical expectation is important to decide that the pennies are not fair.