Send them a copy of "1984" or, i am not familiar with chromebooks, set a bios/boot-password or something so if they want install anything, they have to ask for

Send them a copy of "1984" or, i am not familiar with chromebooks, set a bios/boot-password or something so if they want install anything, they have to ask for permission. I kinda find it helpless to monitor kids activities instead of talking to them, explaining where the dangers are.