My kids both have chromebooks and gmail logins with parental controls applied - screen time limits and the like.

They also have school Google accounts, which they need to be able to use.  These have no screen time limits/etc.

Guess which accounts they always use.

Guess who's clicked on dodgy ads and accepted notifications and ended up with a bunch of "you have a virus" notifications...

Is there a way to apply controls to the whole device, or some other way to stop use of the school account outside certain hours, or ... anyway to thread this needle?