Not all, things like REAL digitial ink, the top end commercial packages, Office, Photoshop, Autocad, the list goes on, not there, at least natively. There's PLENTY that Linux doesn't do.
The only one of these things that's even remotely relevant to a public school education is AutoCAD, and that's a specialized tool that some schools might offer a couple classes in, not something that every machine across the entire school system needs.
In this context, this decision makes perfect sense. Yes, the business world uses Windows, but who cares? You're learning how to type, use a word processor for simple documents and so on, maybe some simple programming - not how to maintain a machine and the ins-and-outs of the operating system. It really doesn't matter what OS is taught, and considering it's public money, I'd rather it not go into further entrenching a giant monopolist's products.
Also most, if not all, the tools they would be learning are available for a bunch of different operating systems (and for free), which in an education context is IMO important. Parents of a student shouldn't need to buy a Windows computer, and a copy of Office so that their student can do homework at home. The tools the student needs to be able to use at home should be as widely available (cross platform) and low cost as is feasible.