Wife is a HS teacher that has access to Chromebooks (CBs): Yes, they are useless. Even if you could get the 35+ kids per class to stop sending each other pics of their sex-organs during class the CBs are still futile. The district has mandated that you cannot use a CB without logging into the main district server. That is fine and dandy, but the wireless routers only have so much bandwidth, so you can only have ~15 kids per router logged on until they are auto kicked off. That then starts a ring-around-the-rosy of kids trying to log back in and kicking others off the wireless. Bonus points because there is only 1 router per ~5 classrooms. The CBs are also on a cart to be used and so my wife has to push that to each class she is in, so trying to get all the CBs out, set up with the lab, logged into, made actually useful, then logged out of and put back, charging, and ready to be pushed to the next room is difficult to do in the allotted class time. There are not enough classrooms in the school for the kids, so they have many 'lunch' periods that kids alternate in so some can be in class while others sit in the hall. Again, this clogs up the wireless routers too. Also, the Mirai botnet clones are still attacking the central district server and causing havoc with trying to log into it to make the CBs useful. As such, its a total gamble if the CBs will function at all on any given day and between classes or within a class period.

Maybe the CBs are not the culprit, but the whole system has made then useless to everyone but the company that sold them to the district. iPads are just finessed off to pawn shops for cash by the kids, so they never really took hold to begin with.