Behind the Scenes: 'High School Musical 3'

"It's the first time that Troy and I actually get a chance to do a number together ... I'm not going to give it away. Surprise is always the best," Bleu said.

With 17 dance numbers in all, "High School Musical 3" has enough high-energy throwdowns to leave even these actors gasping for breath.

"I came into rehearsals a few weeks late -- bad idea. It was tough catching up with everybody. Corbin, who's just the most incredible natural dancer I've ever seen. I mean, Vanessa's tough to keep up with, man," Efron said.

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"I'm still hurting. We're all kind of limping around," Hudgens said.

The day Connelly caught the cast on set, they had just finished 12 hours of straight dancing.

"I think I grew a full shoe size. My feet are so swollen. It's pretty bad, but it's worth it," said Monique Coleman, who plays Taylor McKessie, the leader of East High's science club.

"Well, actually, the shoes are comfortable," Tisdale said. "We had ballroom shoes on and everyone was wearing heels and everybody was like, 'Argh, my feet hurt,' and I'm like, 'Mine are great!'"

Like the earlier films, this one is not being shot on a Hollywood soundstage, but at a real high school: Salt Lake City's East High School.

Even as the last day of shooting, in late June, will be a time for bittersweet farewells, the sheer joy and exhilaration of getting to do a "High School Musical" one more time shows no sign of stopping.

"We all pump ourselves up so much. Like, before the beginning of a take, you'll see us all screaming, 'Whooo! Hooo! Yeah!' Like screaming! And we just get so pumped," Hudgens said.

"But to come back to Utah and be with my friends, it's just a dream come true. I called my mom and dad on the first day and was, like, 'I feel like I'm on vacation.' ... We really are friends and it's pretty fun," Efron said.