German here. Have a kid in elementary school and one in middle school. No phones allowed whatsoever. But to be fair: every school in Germany can decide that for themselves. But when we were choosing schools, all schools had similar rulesets. Some event prohibited smart watches.

Czechia had per school rules as well (my kids school bans them in school premises, which leads to groups of kids starting at phones in front of the school, sad sight), but as discussed yesterday by minister of education it's clearly not effective and still huge part of kids use them during school breaks despite more than 90% school officially banning them.

Czechia was one of the, if not the last country in EU without nationwide smartphone regulation

Btw I can't imagine putting my kids in education system in country where you don't have home schooling alternative to state indoctrination in case you need it. And German 2015 immigration crisis and green deal clearly show us your leaders can't be trusted at all.