Zac EfronWe're on the set with the most popular seniors ever -- the 'High School Musical 3' cuties

OMG! Can you believe it?

The popular crowd of East High is set to graduate, in 'High School Musical 3: Senior Year.' But at least the kids, including Zac Efron and Vanessa Hudgens, are going out with a bang by taking their song-and-dance act to the big screen.

Here are a sweet 16 things you must know before you go. You're on your own for earplugs to protect your hearing from the shrill screams of the tween girls.