As  new instructor a couple years ago, I worried that games would be viewed by the students as silly or a waste of time.  For most groups, though, I've seen games work well to improve retention of dry material.   Currently I have a group of students who are sharply divided in their choice of friends within the class.  I have to be careful with games, because it is toxic to have the competition in the classroom fall along lines of friendship.  The admonition in this series to choose teams randomly is a very pertinent recommendation for me right now.  The last time I assigned a learning activity, and allowed the class to choose their own teams, one student was left out.  Fortunately, he did not take it personally, and when other class members realized their mistake, they tried to include him.  At that point, his work was nearly complete, so he declined. 

I'm going to use the ball toss, baseball, make me a match, and mystery term in my next few class sessions.  I look forward to creating the positive energy that this group so sorely needs.