http://msjensen.cehd.umn.edu/webanatomy/

This site gives quizzes and learning games. I really like this site because you have so many choices as to the type and level of tests you take. You can do self tests, timed tests, and multiplayer games. Once you decide on that you choose the topic you want to take the test on. You can retake the tests as many times as you want and also get a more difficult test each time.