I've mentioned this to a few 3D Modellers and builders that I know recently so it is as good a time as any to post. AutoDESK have a great approach to student training - anyone with a college email address (including staff) can get access to almost the whole of the AutoDESK suite for four years.
Not only does that include AutoCAD but also 3DMax (you might remember the 3D model of the Chapel I tried to get printed) or for people working on models and animation for the computer industry you can download MAYA for realistic environments. I wouldn't fancy trying to draw this in AutoCAD!
All available for free here