What Electr0_90 said, it's illegal if they spy on you without written consent. My college offers windows 10 education for free, but they do not us it to spy on others. It's simply there for students to download a MS operating system, without paying $150 for a home or pro version.
Now if you're also concerned about Microsoft sending too much telemetry from your computer, you can download a free program called Shutup10. I turned of many unnecessary settings from it, and noticed my laptop was a bit faster. But of-course, Shutup10 is optional.