In-class activity that works well when the terms complementary and supplementary are introduced. Teacher hands out a small card to each student and then teacher instructs students to get up and find their complement in the room. Also a good way to partner students up for other activities. This activity involves basic Algebra as well. For example, one student may have a card that says 4x + 70 and they would have to find 20 - 4x. There is a set of cards for complemenary and supplementary.