Most "school bans" that I have seen so far are actually things like, "A teacher-enforced official policy of no using phones during class." In other words, usually the same as the status quo, because what teacher says, "yes go ahead and use your phone while I'm talking to you".

The local public high school makes students put their phones in pouches during classes. It seems good at preventing distraction but doesn't really do much about kids wasting lots of time on social media, sharing terrible material on social media, communicating between classes, or after classes. Probably better than nothing.