Summary: Playing mathematical games enables middle school students to engage their minds while discovering and using meaningful strategies. Blokus[R] is one such game. While playing, students exercise spatial awareness, analyze attributes of two-dimensional shapes, compare patterns, and use logic‒all of which encompass NCTM’s Content Standards. Students must also engage in problem solving for their offensive and defensive plays and reasoning and proof as they investigate and justify their moves. They make connections as they link mathematical concepts and communicate as they record strategies and answer "What if?" questions‒all tenets of the Process Standards. Preservice teachers encountered Blokus while enrolled in a middle school math teacher preparation course. After playing the game, they wrote about the embedded mathematics. They also produced a list of math problems that they could ask future students while playing this game. Some of these creative problems were explored and solved by two sixth-grade classes who played Blokus. Although some may oppose investing classroom time playing a game, one hour of natural learning and true engagement playing this board game created mathematical interest and furthered critical thinking. (Contains 5 figures.) (ERIC)