(FORTUNE Magazine) – Disney Channel's romance between jock-turned-singer Troy (left) and adorable geek Gabriella (below) has gone from TV movie to global cultural phenomenon. What's up with that?

1  What is High School Musical? A made-for-Disney-Channel movie that's part Grease, part West Side Story, only tamer. Geeks become cool, jocks become geeks but remain cool. What's not to love? Especially since it cost Disney only $4.2 million to make, drew 7.7 million viewers when it first aired Jan. 20, and has a soundtrack that went platinum in March.

2  How did Disney Channel manage it? Before the movie aired, the company advertised free downloads in kid-friendly magazines to drive tweens to its website. It produced karaoke and dance-along versions of the movie that aired shortly after the original film's debut. The movie's basketball-based theme song, "Get'cha Head in the Game," is playing at NBA arenas. (Shaq has been spotted singing along.)

3  When did Disney know it had a hit? Before it finished shooting, says Bill Borden, the man behind the movie. Borden, who also produced La Bamba and Spike Lee's Get on the Bus, says the dailies (the raw footage from each day's shoot) disappeared from Disney offices on a regular basis.

4  Will there be a sequel? Disney plans to start production before fall. Expect the book and DVD on May 23, Bollywood and Spanish versions in six months, and actual high school productions by winter.