If you are one of the many readers (more than 100 everyday) of our free DMU tutorials about 3D game creation using WPF , there are good news for you:
Daniel Lehenbauer put available on his blog a converter from Blender to XAML. Now you can create your games using this free 3D modeler.
http://blogs.msdn.com/danlehen/archive/2006/01/14/513012.aspx
Soon we will present a complete tutorials serie about the use of Blender and the Daniels' converter. For beginners in 3D modeling.
I believe that we have here a good system (Blender+WPF) to teach the basics of game creation for students. And all FREE! (if the school has Windows XP, of course).
WPF is not a professional game engine (I like to repeat this again) but it's good for hobbyists or students. That can publish, using the free Visual C# and ClickOnce, their works at the internet.
Thanks Daniel.
Our tutorials (good for Dec CTP) are at:
Blender is available for download at:

Good news: Blender-XAML exporter