If you haven't seen the episode of
South Park called "The Ring", you ought to! It had some interesting things to say about how we sell sex to preteen girls.
http://en.wikipedia.org/wiki/The_Ring_(South_Park)
Girls these days face a lot of overt and subtle cultural messages about sex and what it means to be sexy, as well as what it means to be feminine. There's a reason why VS's line for "teens" (yeah right) is called Pink; gender traits are more emphasized in marketing for teens, and femininity in marketing is strongly associated with youth. The blatant trend toward marketing for preteens is disturbing. Kids are growing up way too fast, and some parents don't seem to have a problem with the oversexualization of their teenagers.
Ugh.