What should my tittle be?

You make a good argument IF and I mean "if" the user is a responsible person. The problem is that the few abusive users will interfere with the rights of others, no matter how small their numbers are. It only takes one ringing cell phone to disrupt the entire class. All students are guaranteed their right to a public education and teachers are protected by law from any interference while performing their jobs. The quality of public education is of major concern in this country. You have perceived the cell phone as a "necessity" at school but it is not necessary. It is just something you desire to have at your disposal. Your rights end when they interfere with another person's rights.