Well, presumably 100% of Chromebooks are sending student data to Google; whether or not that qualifies as "third parties" and/or "consent" is debatable.
Person in US school system here. I’ve had to use Chromebooks for school, and all I can think about is what Richard Stallman would do if he were in the US school system right now.
I told him about part of a local school district. He politely told me, if he were a student, it would make him hate the system, even though the rules are very reasonable.