I'm looking at doing something similar (but
simpler) with my 7yr old. It
struck me that the end product should actually 'do' something,
having a finished product that is a computer is great but being able to get
it to control something - eg r/c car, robots, bedroom lights, model railway
might well fire a child's imagination even more.
That's a darn good idea!. Every kid these days knows what a computer can
do :-). But having one control an actual physical device is something new
to them. And as was discussed last week, it;'s a lot easier to do
interfacing hacks on a classic machine than on a modern machine with PCI
and USB and not a lot else :-)
I don;t know where you are located, but if you're in the UK, you might
want to look at the Maplin toy robot kits. They do a little 2-motor 6
wheel chassis kit (no electronics) for < \pounds 10.00 which looks ideal
for computer control experieemnts. I am currently contemplating using
some classic HP interface hardware (HP59306 relay box HP59313 ADC, etc)
to control such things, but that's certainly not what you want to do.
-tony