Mastermind

I read this post about using Mastermind to teach proofs and logical thinking. I've been meaning to introduce the game for a while in my high school geometry classes for a Mastermind Monday (along with Tangram Tuesday), but didn't get around to it until yesterday. As I introduced the game, my students paid close attention, which is not always the case when I am talking. I tried to use the language that Avery describes on his blog post, but I had a hard time with it. Instead, I asked students after their gave their guess, "What was your strategy?" or "What were you thinking when you made that guess?" If I heard students say something like, "There's not a 1 in this game" or some other conjecture, I would ask them to repeat it for everyone to hear. There were individual arguments over what to guess next more than whole class discussions. I need to work on making sure the class is all involved equally in the game, as well as work on having them make conjectures rather than just describe a strategy. Otherwise, the game was fantastic! The first time we played, every students was engaged. Their minds just latched on. In every one of my four geometry classes they asked to play it again today, and we did. This game is absolutely becoming part of my regular arsenal of activities.