Richard writes -

Where simulations are interesting and even exciting teaching tools is in the other extreme -- where the mapping from real to virtual is uncontroversial, but the consequences of these known interactions are unclear. This is generally the case when we are simulating physics.

A nice, small non-technical and generic explanation of a physics SDK can be found at: http://opende.sourceforge.net/slides/slide1.html Also happen to like the presentation's aesthetics. The author, Russel Smith, created the Open Dynamics Engine (ODE): http://opende.sourceforge.net There is a Python wrapper to ODE, but for some reason the link is not working. So I will mention that there is an extant copy of a Windows binary for PyODE and Python2.3 which I had compiled, and made available some time ago at my own site: http://pw1.netcom.com/~ajs/download And, yes, I agree. Art