But if kids refuse to put their phones away during classes, teachers have no right to take them since they are the kids' personal property. And yes, it is in the school rules that you cannot use your phone during class.

My SO teaches English and struggles with it permanently. Kids are on their phones and not paying attention to the lecture. And no support from the headmaster. Other teachers claim they do not have the problem to save face, but then you talk to an expat teacher who was in their class for observation and hear something else.