Continuity mistake: As Zach is 'raising his goblet of rock', his hand gets a lot lower in a shot change. (00:40:10)
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School of Rock (2003)
Ending / spoiler
Directed by: Richard Linklater
Starring: Jack Black, Joan Cusack, Mike White, Adam Pascal
The principal and the parents find out Dewey is not a sub and he leaves before he gets arrested. The kids leave school, get Dewey and go to the Battle of the Bands. They sing a song Zach wrote himself, but they lose to Dewey's old band. The crowd cheers for The School Of Rock, and they play another song. Dewey winds up running his own rock-music lesson studio with Ned.
Keylime
Ms. Mullins: I've just been informed that all of your children are missing.
Trivia: Miranda Cosgrove, who plays Summer Hathaway, actually has a good voice and plays guitar. She had to take a 45-minute class to learn how to sing badly for the scene where she sang "Memories."
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Answer: It is never said but If I was to guess, they got it from the guy he was pretending to be (Ned's) information from the school office.