vPython looks like a great tool for at least part of the job, assuming it runs under Linux (I couldn't tell from the website). I'd need to have something kewl from a kid point of view, but educational from a parent point of view.
It does run under Linux, although I don't maintain the linux version. See http://cil.andrew.cmu.edu/projects/visual/download.html#linux. Let us know if you need any help with visual - I'm rather busy at the moment, but this seems like a good cause so I'll do what I can.
But this first one is just propaganda, just like Microsoft's dog and pony show.
Even in propaganda, you might mention that a key advantage of open source, python, visual, etc. is that students and teachers can actually get involved in content creation, rather than just absorbing the content bottled by %(company)s. Dave