This case study is based on the game theory developed by John Maynard Smith where two behavioral strategies ("Hawks" and "Doves") compete over a contested resource. During this 50- to 75-minute case, students experience "hands-on"' the change in frequency of the behavioral strategies by playing the game Rock-Paper-Scissors and documenting the results using clicker responses. Through this simulation, students explore ideas of natural selection, evolution, evolutionarily stable states, coexistence of behavioral strategies, and frequency dependent selection. The case can be easily adapted to focus more heavily on one or more of these different aspects of evolution by natural selection.  In addition, the case provides an opportunity for students to confront misconceptions they may have about evolution and to learn about possibility of coexistence between aggressive and non-aggressive phenotypes. This case study is ideal for a large introductory ecology or evolutionary biology course where the students are familiar with basic background concepts in individual ecology, evolution, natural selection, and evolutionary fitness.