I was cycling (i.e. in the road) (sometimes walking, not in road) to and from school 2.0 miles away at that age. This was before/as phones were only just becoming interesting to that age group (getting MP3s and ringtones etc.), I think I didn't have one at first and then did, but I begged for it, it wasn't forces upon me as some sort of safety ('parental leash'?!) device.

What're you actually concerned about? Is that going to helped by your child having a phone themselves (vs some bystander)?