Things like this make me cringe for one reason: the lack of standardization, in terms of enforcement and “who gets searched” vs who is left alone.
That lack of standardization turns things like this into an excuse, or at least an opportunity, for unfair treatment of certain groups.
“I saw that white kid with a cell phone earlier, but I’m going to let it slide because I don’t want to be an overbearing teacher.”
“Uh-oh, that black kid looks shady and is probably using that cell phone to deal drugs, better search him.”
(I’m realizing now that I’m showing my age by assuming cell phones are still disallowed in schools, substitute whatever is currently disallowed, maybe pogs or something?)
I’m not saying every teacher is an evil racist, but when you leave something like this up to “gut instinct”, personal prejudice quickly becomes institutionalized prejudice.
On the other hand, student’s rights are a pretty funny concept. You’re at an age where you’re not quite children anymore, so you buck against the rules that apply to children, but from society’s perspective, you’re still a bunch of kids. So “movements” like this don’t last very long, especially because in a couple years when you graduate, you won’t care anymore either.