I'm considering teaching a class on open-source computer graphics at my church to 10-20 yr olds or in the local high school night program.

I've played with Knoppix for over 14 months now and I myself know how not to wreck the underlying installation; I am wondering if one were intent on doing something stupid, one could find a way. I just have fears of giving a knoppix (or Mediainlinux, 'cuz they got povray :P ) CD to an 11-year old, and he finds a way to reformat his father's work laptop. I wouldn't hesitate to give to 18 year olds, but younger kids might go nuts.

Two questions:
1) Is there a way to minimize the risk of such events by choosing a particular distro (like, is Gnome less risky in this regard??) or some other means?

2) Is there a common articulation of the risk available somewhere such that I could give to parents with a CD?

Thanks.