And you call yourself "GovernmentShrinker?" (hint - cell phones are expensive private property)
Yes, I'm very much a GovernmentShrinker. If it were up to me, there would be no such thing as a public school. But that seems to be out of my hands, and at the moment we're talking about MY tax dollars and YOUR tax dollars which are being spent to the operate the abominable public skools. Those dollars are not "private property" after they've been confiscated from us by the government.
No one is forcing these kids to bring their phones to school (unless their parents are, and no one is forcing the parents to force their kids to bring phones to school). They have been offered a no-cost way to hang on to their phones, but it seems that quite a few of them would prefer to steal educational opportunities from their classmates and from the taxpayers who have been forced to finance these opportunities, than to turn their cell phone ringers off during class.
They just CAN'T remember? Hah! Try my method and after a few kids have been relieved of their phones and had to explain to mommy or daddy who paid for the phone why they couldn't turn the ringer off during class, all the rest of the kids will miraculously discover how to remember to turn off their ringers during class. Right now, they just don't WANT to remember. As soon as not remembering becomes synonymous with not having a cell phone while most of your peers have them, they will WANT to remember.
Of course, an alternative method that's worth trying first, is to refuse to give the phones back the KIDS. For first offenses, tell the kids their parents can come pick the phones up from the principal's office anytime during school hours. There won't be a lot of second offenses, and if the second offense policy is that the phone doesn't get returned at all, third offenses will be very rare indeed. In nearly every case, the parents have paid for the phone and have financial responsibility for the service account, so it's THEIR property, and they are legally responsible for how it's used.