Friends of ours lost their 17 year old daughter last year.She stopped alongside a truck waiting at a stop light,she was on her bicycle, listening to her I-pod,despite her father's warning about the dangers of such things.The lights changed,the truck turned right,she went to go straight.She neither saw or heard the truck pull away.
I don't need to tell you the rest.

My own son won't listen to anything, even when he's driving in the car;says he likes to be aware of what's going on around him.

David