I am all for teaching a game that requires critical thinking skills. Chess is different than most games, it focuses purely on strategy and since it is an even playing field with no luck mechanics, the better player will always win. With it being a class, I am going to assume passing will depend how well you do in it. This will encourage students to outsmart others by coming up with new strategies and adapting to better opponents. Developing such critical thinking skills will help them later in life to succeed.
Unlike the FPS game nowadays (i.E. Call of Duty, Halo, etc.), chess requires strategy. You don't simply aim and press a button. This game of wit might be slow-paced for some, but it can be truly appreciated by people who actually play games to exorcise their minds. (I like Call of Duty, just to be clear. The ultimate purpose of a game is to have fun. But chess combines fun and smartness, which is great.)