i had always figured it had to do with their skin...i.e. the reason fashion designers like to use 13-14yr olds is that, unlike their older counterparts, they still have flawless skin, wheras, past that age,regardless of how well you look after your skin, you will still get some pimples etc...which leads to minor flaws in the skin. meh... i'll just let chris hansen and pedo bear do the talking.