I would second the Etymotic MC5 suggestion.
Good sound quality, the Best Isolation, and fitted with a small size Comply Foam Canal Tip... Very Nice, all day comfort.
The Ety Kids model due have a smaller barrel diameter, But what biker wants to say... I got the Ety Kids model.
Buy em, Try em, then if he doesn't like em... Take em back.
PS Look up the Comply Canal Tips on the Complyfoampro.com site.