Either that or the kids found workarounds. I never had to deal with any of this myself, but I remember that being pretty common back in the day. Some you could even just ctrl+alt+del and close it in the task manager, do what you wanted, then open it back up to make it look like nothing had changed, though the parents would have to be technically competent to some degree to even check for that.

I think the systems these days are better but probably still aren't foolproof. Decent chance one of the kids even shoulder surfed or otherwise figured out the password, or maybe just found the parent's device unsecured and removed the limitations, which would be consistent with the claims of setting them one day then a few days later they are just gone.