> Most guardians would willingly do similar with locked devices.

Considering the echo chamber in which I was at school, my friends would have simply used some Raspberry Pi (or a similar device) to circumvent any restriction the parents imposed on the "normal" devices.

Oh yes: in my generation pupils

- were very knowledgeable in technology (much more than their parents and teachers) - at least the nerds who were actually interested in computers (if they hadn't been knowledgeable, they wouldn't have been capable of running DOS games),

- had a lot of time (no internet means lots of time and being very bored),

- were willing to invest this time into finding ways to circumvent technological restrictions imposed upon them (e.g. in the school network).