1 / 8
In this photo provided by StarPix, actress Miranda Cosgrove stops for a photo at a Seventeen magazine event, Saturday, June 25, 2011, in New York. (AP Photo/StarPix, Dave Allocca

Slideshow: Young stars who look mature

They're teenagers? Really? Forget overspending at the mall, exceeding cell phone minutes, and staying out past curfew—today's famous teens are living large and dressing the part.