School is supposed to be about learning, I guess.
With that in mind, I think the right idea is to go for a proper SLR. The EOS 20D is a great suggestion. You can start out in green box mode, and gradually broaden your horizons to full manual as you begin to understand the limitations and abilities of the system.
One great thing about it is that the rig you buy secondhand will maintain a lot of its value, so you can use it or a while, get extra lenses, whatever. When you feel the need to upgrade (or *gasp* give up being a tog!) you can sell the stuff for nearly what you paid for it.
A P&S like a g10 or g11 might give you decent results, but you won't learn much about the craft.