So, I grew up in the early 2000's as far as secondary schools are concerned, the rules were simple, bring it out during class you'd lose it, unless you told them you were expecting an important call in advance or something, which case you might be alright.
Heck, we couldn't even have cards on us technically, got mine taken when I was 17.
And as far as phones go at least, fair enough tbh, I'm not a big fan of what modern social media does to people anyway, so I'm biased, but in a school setting it does make sense that phones should be off/silent during class, outside of emergencies, they don't bring anything of value to studying, maybe if there was a school mode that could be activated, allowing calls from parents exactly, and making certain apps unavailable during those times, it could help?