What Did One Angle Say to the Other Angles?

Activities that lead students to discover some interesting and perhaps unexpected results are fun for both students and teachers. Here, Fairbairn presents an inductive angle-sequence activity that uses paper folding to arrive at a surprising conjecture and provides two versions of a second activity leading to deductive verification of the conjecture. Although these activities are suitable for individual effort, Fairbirn finds that having students work in small groups of three or four students is more enjoyable for them and thus have formatted the activities for group effort.