whether school should ban mobile phones

whether school should ban mobile phones
this a freely topic.you can talk whatever you think.of course ,you must give our reasons.it is a three-minute speech!

Nowadays,practically everyone has a cell phone,and most would agree they are a great convenience.Still,they are the subjects of tremendous controversy.Do they cause cancer?Do they cause car accidents?And perhaps most importantly for millions of students,should cell phones be banned at school?
Many students depend on cell phones to coordinate plans with their friends and family.Mobile phones are especially useful for obtaining rides home from after-school activities.In that context,cell phones most definitely should be available for student use on school property.The question is where and when may they make calls.
The smartest move is to let all students keep their phones with them on campus,but to ban cell phone use during school hours.
Certainly,people shouldnt be gabbing it up with their friends during a lecture.Cell phones are a luxury-- not a necessity-- for students.Class is a time and place where learning should take priority over everything else.Cell phones do not belong in the classroom,but that doesn't mean they shouldn't be allowed at school.
So what's the point of having cell phones on campus if students can't use them during school hours?The availability of convenient communication.Most schools have pay phones at students disposal if it becomes necessary for outside contact to be made,but these phones are nowhere as immediate or convenient as a cell phone.
Letting students carry phones on campus allows them this freedom.However,whether schools do the right thing and avoid complete bans on cell phones is strictly their call.