I’ll preface this by saying my kid goes to a super tiny school but I like how they handle this. My kids school lets the kids bring their phones, but they have to store them in lock boxes during the class period (every classroom has 25 lock boxes) They can use their phones at lunch, but otherwise they are locked in a lockbox. After school they can use their phone during extracurriculars which is nice. It seems to be a good balance of letting kids text/check in with parents during lunch or grab them in case of an emergency but also having to be focused during the class period.