This article describes a simple classroom activity that illustrates how economic theory can be used for mechanism design. The rules for a set of contests are presented; the results typically obtained from these contests illustrate how the prize structure can be manipulated in order to produce a particular outcome. Specifically, this activity is designed to show how changing the prize structure can impact both the contestants' average efforts and the effort level of the hardest-working contestant. The activity can be run in a 50-minute class, has instructions that fit on a single piece of paper, and, although it can be run in large classes, requires only six students. (Contains 1 figure, 2 tables, and 5 notes.)