Cell Phones in School?

In school we should be aloud to use cell phones as long as it's on our time not the teachers when we are learning. Like in lunch or advisory, or even when we are done with a test or quiz. Or just have nothing else to do. Just as long as we have them off when it's work time. Because what if there is an emergency with your family, or something at the school and there is no phone around. You could just pull out your cell phone and call your parents or the police, whoever you need to call you can. If not there's going to be big problem. So why even take that risk? If your in trouble, or your sick and you need to go home. What are you going to do? Go to the nurse and wait 20 minutes until you can go home? Or text or call your parents to come get you and you wait maybe 5minutes at the most. When you forget something at home you have to go to guidance and use that phone that your parents don't even pick up when you call or call them from your cell phone and they know it's you so they pick up and get what you need. Or the same thing with lunch. You forget your lunch money or your lunch from home on the counter and you have to wait until lunch is over to get it because you can't just text your mom or dad from your phone. You have to go to guidance again and call from there. Then your hungry all day. All because you just cant use your cell phone to call your mom or dad to get you stuff. So we should be allowed to use cell phones on free time and emergency purposes. But it has to be turned off in class when we are learning.