"What Time Is It?" is the opening musical number and first single from the Disney Channel Original Movie High School Musical 2. It is featured on the High School Musical 2 soundtrack, and is the first song off the High School Musical 2 soundtrack.

The song had its world premiere on Radio Disney on May 25, 2007 as part of its Planet Premiere featurette. On June 8, Disney premiered the video as a sneak peek in multiple nations at close to the same time. The single was released on July 16, 2007 worldwide, and on July 17, 2007 in the United States.

The song was supposed to be played during the Sydney Harbour New Years Eve fireworks on December 31, 2007. But due to the music breaking down, it never got played.

The song's video clip and the sequence in the movie commence with the whole of the East High Wildcats in a classroom. On the blackboard in that classroom, a photo is visible with Sharpay and Ryan Evans performing "Bop to the Top", next to where it says "School's Out!" A poster for the East High Winter Musical, "Twinkle Town", featuring Troy Bolton (Zac Efron) and Gabriella Montez (Vanessa Hudgens) is also visible. When the clock has ten seconds to go before the bell, the class commenced chanting "summer!" getting louder until the bell rings, after which the song is performed. The music video contains clips directly from the movie, and was released on July 31, 2007 on the iTunes Store. The music video was also released on the Disney Channel.

The song peaked at number 1 on the Billboard Hot Single Sales chart for 28 weeks, which became the highest selling single of the year-end chart in 2007.

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