These classroom games were created in PowerPoint and LOOK very attractive and user-friendly.
Download the templates and modify the games to fit your curriculum needs here.
Lots of whole class participation games similar to Jeopardy,Wheel of Fortune, Pyramid, Are You Smarter Than A 5th Grader?, Password, Who Wants To Be A Millionaire?, and more.
Feb 2012: I just found another site with 52 more power point game templates. Click here.