ylian1007, a search on "K-12 schools linux" and "schools linux" gave several sites. Here's one that looked pretty good:
Also, you wanted a distro that would be able to use commercial apps. I'm afraid Wine is the only option that works well within linux. It's a Windows emulator, and some distro's do it a little better than others.
If you would search the Inet with the terms "__app__ linux wine" you might be able to determine if it is feasible to run your applications on the linux platform.