Games offer more than just fun and play, and the analyses suggest that varying vocabulary activities is important if learners are to practice all the aspects of word knowledge. However, despite all the evidence, just claiming that playing games is a good way to practice the language is often not enough to win the argument. Because author Nico Lorenzutti's in-service teachers needed a specific rationale to explain what their learners achieve when they play games, he created a simple tool to explain what learners achieve when they play games. This article describes the procedures for several games and illustrates how to use this tool to assess their overall effectiveness for vocabulary development.