Dear principal i think that you should be able to bring your cell phones to school because if your mom or dad is trying to contact you because of a family emergency and your phone is off than they might get worried and panic. And if the students have there phone out during lunch than it's ok but if they have it out during class than the teacher can take it away and send it to the principals office. And the principal can take care of it and call the parents and tell them that your kid was using his/her phone during class so we had to take it away from him.

When it's lunch or break time than they could call their parents or whoever their parent is and ask what's going on and if it's nothing serious than they don't have to worry anymore. But if it's serious than they could go to the office and ask them if they could leave but it wouldn't be ok with the office because your parent has to be at the school to sign you out for example yesterday my mom came to school to pick me up early for an emergency so she had to go in the office to tell them that i am here to pick up my kid.