The cylindrical mirrors lab described in this demonstration has been done in many forms. However, because of its ease in construction and variation, this version allows students to do the exercise themselves, thereby capturing that sense of confidence in using a scientific law to predict outcomes themselves. It was found with this activity that students experimented on their own, changing different variables in the setup and sharing their results with other members of the class. Groups would come up with scenarios to test and get other groups to try different ones; it became a collaborative effort by the class as a whole to try all possible arrangements.