In 1977, kids' network Nickelodeon debuted (as Pinwheel), featuring completely unsexy programming for youngsters. And today? Nickelodeon itself adheres, mostly, to the kiddie concept, although the focus is now on young adults. Since the early 1990s, the network has been super-successful with a string of shows about and for tweens and teens. 

But you know what? Tween stars grow up. Girls who were cute ten years ago are women now, and they're cute women.

We're pretty sure the board of directors never called a meeting where they announced "Okay, now we're going to start making sexy starlets." They didn't call that meeting. But they do make the sexy starlets, and have been doing it for years now. They can't help it—kids grow up. Happens to everyone.

This weekend, Victoria Justice of the now-canceled Nick show Victorious puts her big-girl pants on for Fun Size, in which she plays an older sister who manages to lose her little bro on Halloween.To celebrate this new phase in Victoria's career, here are the 20 hottest Nickelodeon stars, past and present.

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