Current age: 28
Career at 20: Zac already had scores of screaming fans in the wake of High School Musical. His heartthrob status exploded with the releases of High School Musical 2 and Hairspray, both coming out the year he turned 20.
Relationship status at 20: Zac's lengthy relationship with High School Musical costar Vanessa Hudgens was wildly publicized.
Quoted at 20: Zac called into a radio interview with Ryan Seacrest and talked about his sudden fame: "Your day requires a little more planning. I used to be spontaneous, but now it's like, 'Ugh, do I really gotta go outside?' But you know, I'm getting used to it. Dude, when I take a step back and look at the big picture . . . It's worth it. I get to do what I love. I think that it's definitely worth it."