That's just an arms race. The kid will find a new favorite website to play games on, there seems no end to them. There's endless websites out there that are more appealing than doing homework. I have a very locked down network, there's always some new website that has games of some sort to play.
If schools are going to provide these things, they should have the sites the kids might need to access white-listed and block everything else. Telling parents to try and block things is not realistic.
With SSDs costing under $50/TB now, it's hard to see why you couldn't put everything the kids need onto the laptop itself. The entirety of Wikipedia with pictures is 110 GB. Throw in a selection of reference books, videos, and software, and there's essentially no reason to have it go online. Provision it with the full year's worth of material at the beginning of the year and that's it.
Definitely agree this is possible and a great idea, but I think one challenge might be if you need access on a school laptop to do the majority of the homework. Not sure if that’s the OP’s case
If schools are going to provide these things, they should have the sites the kids might need to access white-listed and block everything else. Telling parents to try and block things is not realistic.