As a student (over a decade ago) I had hundreds - maybe even thousands over the 13 years of education, actually - of phone calls with my parents, siblings, grandparents, uncle, friends etc about various stuff I was doing after school, during school (and sometimes instead of school).
I'm sure the school office would've loved to handle all the calls for us, lol.
I'm not even arguing kids shouldn't have a phone at all (OP is talking about during school hours), but even so - why would you ever expect the office to do that? Communicate with your parent/child before school to make a plan or establish a routine for meetups as was done for decades before smartphones.
It's a fig leaf rationale to keep phones in children's pockets during class.
You said that if there is a legitimate need they can call the school office or have the office call the parents - so I'd expect the office to handle it.
For myself it was mostly that parents could simply call me 5 minutes before they picked me up for my dentist appointment (which I had at least monthly for 7 years due to having braces) instead of me waiting somewhere for who knows how long because there was a traffic jam (and missing more schooltime than necessary).
They could simply call me/send me a SMS and ask me to pick up my younger siblings when they had unexpected work and couldn't make it in time - but since they respected me as a person, I had to confirm that I will do it and don't have other plans. Obviously, if I saw the question only after school that'd be way too late and they would have to force me into it instead of simply asking the grandparents if I said I can't.
Because why the hell shouldn't we use modern technology if it's available to us? Thanks to it we were flexible, and we enjoyed it.
Yeah, I also used the phone during class. Because the lessons were shit. Though we had a few very engaging teachers and even though I had zero interest in their subjects, I never used phone in their class.
Schools have to improve, taking phones away is just bandaging the symptoms.
Good point. I am in the United States. Here, student’s rights are significantly curtailed when they enter a public schools building, and - generally - districts have the legal authority to restrict behavior that "materially and substantially interferes" with education. If school districts in the US want to go “zero smartphone”, their problems would be cultural/political - not legal.
I'm sure the school office would've loved to handle all the calls for us, lol.