My solution to the school win/mac dilema is to do what I'm currently doing: make a client/server educational piece of software over a "single player" version (ie the dreaded edutainment ).

The way I see it, you can make your server on any box you want (in my case, 3DGS windows ) and then make clients in whatever box you want (win or mac).

I feel this offers maximum flexibility since even if you have all macs in your school (as has been my experience at the uni level), you would only have to buy one win server box and then deploy all your clients on macs.