What can I say, I dislike how the competitive nature of games can turn so nasty in the classroom. In one class period, we can have both Jekyll and Hyde, and when I see too much Hyde, I get stressed out. But I also know from the results of my student surveys that next to story-telling and story-asking, games are the highest-rated classroom activities that my students enjoy and they feel that they help them learn (I suppose some games do). Of course, the key to making games work is to set clear expectations, especially with regard to behavior and sportsmanship, so that nasty competitiveness of Hyde does not occur.