Comment Windows XP (Score 1) 360
Your argument against Windows XP is that it's end-of-life and not supported, and that you don't want kids to learn out dated OS? Good points; and as much as I like Linux. The average end-user is too stupid to use it; and 95-100% of these kids ~WILL be average end-users. At the very least Windows XP still resembles Windows 7, and whatever Windows operating system that they'll be using in their mind-numbing boring and mundane jobs as adults. Prepare kids for what is really going to be used in the real business world, not the IT world, not the developers world but the unidentifiable pointless jobs that the mass majority of them will be working for the rest of their lives.
They might as well start getting mad at their computers crashing, getting viruses and working slow now so they'll be used it it as adults. :p
Next; if you go the Linux route, who's going to support their systems? Is the donated TCO really worth installing an updated Linux VS a outdated Windows?
Clean up the OS, install a freeware firewall, anti-virus, internet monitoring system. The system will at least be able to play the games and educational programs that they need to use.