They don't need to use them in class, but they still need them on their person in case a gunman comes on campus.

They don't need them durning class (with rare exceptions) however, they need them outside of class & too many schools take 0 responsibility for any of a kid's items during the school day, so leave it in the locker & they get stolen & the school says it was the kid's fault for owning a phone.

Fair. That's pretty much my kid's school policy.