Whitelist sites instead of blacklisting? I'm also not sure how kids are getting admin rights to install a VPN in the first place. For the overwhelming majority of cases a kiosk like experience should suffice, which should virtually eliminate any jailbreaks.
Yeah, this never made sense to me and I’ve suggested it to the district, especially for lower grades. They will never block all of the websites they need to unless they block all of the websites. Allow teachers to unblock specific sites for the students they’re responsible for.
If you're using a whitelist approach, you may as well just turn off the internet. Maintaining a whitelist is almost hopeless. Turning off the internet isn't a bad idea, but it is a big change. Maybe some form of archiving interesting pages for kids to look at, but even that feels like too much work.
Plus, if you're using the google docs ecosystem, I suspect it's hard to avoid kids chatting in shared text files, and eventually figuring out how to get spreadsheets to fetch webpages for you.