You might like to try Alice 2.0 (http://www.alice.org/).
You might talk your computer teacher into using it in class, too :)
It's as much fun as a game (and can be pretty adictive!!), it's free, Mac and PC, and you get to program your own 3D environments.

One of the best parts--they are going to bring the Sims content to Alice soon! (in version 3)

If you're having trouble saving the videos to post them or share them PM me, I can help.

-Kit-

Ummm..... what do you do?
i kinda need to know about it before i download it lol

I agree with Jamz.

It's a free 3D programming environment by Carnegie Mellon university. You make your own worlds. www.alice.org


Alice is an innovative 3D programming environment that makes it easy to create an animation for telling a story, playing an interactive game, or a video to share on the web. Alice is a teaching tool for introductory computing. It uses 3D graphics and a drag-and-drop interface to facilitate a more engaging, less frustrating first programming experience.


In the future...

Carnegie Mellon is pleased to announce that Alice will be teaming up with characters from Electronic Arts' hit video game, The Sims™ 2.


Like I said, it's not exactly a game, but it's really cool and someday they will add "multiplayer-support" stuff. If you want to design video games like VMK someday, I think you should start here :)