Here in the Netherlands the government gave the strong advice to schools to ban the use of phones in classrooms. They did not go as far to make it a law, but schools are free to enforce the rule however they want. Some ask that students have to put their phones in their lockers. I believe this is a good step by the government, being someone who grew up in the starting era of mobile phones during high school. I for sure think it has rotted my brain, as I find it hard to stay away from my phone if I am even slightly bored.