Whether it's Chrome OS on Chromebooks or Windows 10 S for educational use, you're pretty much out of luck as they happen to contain the privacy violation stuff that cannot be disabled. You may as well study traditionally if you will and even then, your own electronics are obviously not allowed in schools. In tertiary schools like universities, it may be a different story.
Windows 10 S is said to allow apps from Windows Store to be opened whether it's a Modern UI app or a Win32 app. Problem is, anything outside of that won't be opened and the worse thing is that the computers using Windows 10 S are unlikely to be using ARM-based processors. Windows 10 computers and tablets with ARM-based processors using Windows 10 Mobile will soon open doors to using X86 apps although it can be a bigger disaster for Windows Phones as many of the traditional apps are not touch-friendly.
Citrix's Receiver is a bigger rescuing solution. It allows you to use X86 apps on Windows 10 Mobile, Surface Hub, Hololens, IOTs and even Windows 10 S devices. It is useful for tablets, Surface Hub, IOTs and of course Windows 10 S computers but for Windows 10 S computers, the only handy thing about this solution is that students can go to Chrome, Google search engine, Microsoft Office desktop version and other tools needed depending on the course taken. But still, Windows 10 Education Edition is a better bet than Windows 10 S when it comes to educational use in tertiary schools and policies like GPOs still have to be implemented as part of computer deployment for school use.
What about computer labs in elementary and middle schools then? Will they use Windows 10 S or what? I may be sure that edutainment software is NOT likely to be compatible with Windows 10 S so the Education edition is a BETTER CHOICE FOR THOSE COMPUTER LABS!
I'm sure that there are still IT technicians handling computer stuffs in schools regardless of the educational level of whatever school they're in like they handle the policies, student accounts, software for educational uses and even the edition of the OS for educational purpose. Hell, there's even the school network but depending on the school, either the student's computer gets it connected by the technicians or maybe it's a computer in the lab that is immobilized already set up by them.
Privacy protection-wise, you can choose to exclude the default Modern apps but the problem is that Command Prompt or Powershell WON'T BE SUPPORTED! It is good that way considering the fact it is an edition for educational use and prohibition of those tools is due to user misuse or some kind in which one specific stuff will deliver greater technical damage without the student's knowing. Not even Linux OSes obtained from the Windows Store will be supported as well as if they're too complicated or something.
Lastly, upgrades to Pro edition are reasonable in tertiary schools but there are already hopes and lessons in keeping students cautious on what to do and what not to do to the school computers. There are already better solutions for educational uses out there like using Chromebooks or perhaps using Windows 10 Education Edition. Even better about Windows 10 Education Edition is that it is based on Windows 10 Enterprise so that the IT Professionals in schools have full control. Hell, there's even the Pro Education Edition which removes Windows Store, Windows Spotlight and Cortana by default. At least you won't see any student making some stupid noise or nonsense to Cortana that way, otherwise, the main fault may go to the IT people who allow Cortana to be enabled.