Don't They Just Play Music?

In a follow up to yesterdays post:

My son brought a note home for a big school excursion this week with a list of things that were 'acceptable' and 'unacceptable' to bring for the long drive. iPods were 'acceptable' but portable DVD players and mobile phones were 'unacceptable'. When my wife brought this up with the school, the teacher responded 'iPods, don't they just play music?'