That's fair, but there's another problem. It's hard enough to find a regular educator that's qualified to teach kids about computers on a Windows or Apple. Linux is going to be easier?
The education sector has already bought into Chromebooks, which means that most in-class technology solutions are going to target the browser. The only thing anyone will need to learn to move between OSes is: how do I turn it on, where's the button to launch the browser, how do I turn it off. Everything else will already be familiar.