School of Rock

Rock band No Vacancy performs at a nightclub three weeks before auditioning for the Battle of the Bands. Guitarist Dewey Finn irritates his bandmates with on-stage antics, culminating in a failed stage dive that abruptly ends the performance. When Dewey arrives for rehearsal the next day, he discovers he has been replaced by another guitarist. Dewey's roommate and best friend Ned Schneebly, urged on by his domineering girlfriend Patty, tells Dewey he must pay his share of rent. While attempting to sell some of his equipment for the money, Dewey answers a phone call from Rosalie Mullins, the principal of the Horace Green prep school, inquiring for Ned about a short-term position as a substitute teacher. Desperate, Dewey impersonates Ned and is hired. On his first day at the school, Dewey adopts the name "Mr. S" (stemming from his inability to spell Schneebly) and behaves erratically, confusing the class.
After overhearing the students in a music class the next day, Dewey devises a plan to form them into a new band and compete with No Vacancy in the Battle of the Bands. He recruits Zack Mooneyham as lead guitarist, Freddy Jones as drummer, cellist Katie on bass, Lawrence on keyboard, and himself as lead vocalist and guitarist. He assigns the rest of the class to various roles of backup singers, groupies, and roadies, with precocious Summer Hathaway given the role of band manager. The project takes over normal lessons but helps the students to embrace their talents and overcome their problems: Dewey bonds with Lawrence, who is worried about not being cool enough for the band; Zack, whose overbearing father disapproves of rock music; and Tomika, an overweight girl who is too self-conscious to even audition to be backup singer despite having a strong voice. Band groupies Michelle and Eleni name the band "The School of Rock".
Two weeks into his hiring, Dewey sneaks his key band members out of school to audition for Battle of the Bands while the rest of the class stay behind to maintain cover. The group is rejected because the bill is full; Summer tells Dewey to deceive the staff into thinking that they have a terminal illness, allowing the band to audition. The next day, Mullins checks on his teaching progress, forcing Dewey to feign teaching the actual material. Dewey later meets with Mullins to set up the competition under the guise of a field trip; the two bond over her love of Stevie Nicks.
Ned receives a paycheck in his name from the school, realizing that Dewey impersonated him. Patty pressures Ned to reveal the truth and reports Dewey's scheme to the police and Mullins. During a parents' meeting, the parents question what Dewey has been teaching the kids before Ned, Patty, Mullins, and the police confront him. Dewey reveals his true identity and is fired. Back home, he and Patty argue until Ned intervenes and suggests Dewey move out.
The next morning, the parents confront Mullins at her office, while the kids decide not to let their hard work go to waste; they go to Dewey's apartment and rally him to join them. Ned decides to attend the show and ends his relationship with Patty. When the new substitute discovers the kids missing, she informs Mullins, who races to the competition with the parents tagging along. A school bus comes to pick up Dewey, who leads the kids to the Battle of the Bands and decides that they play a song written by Zack earlier. Initially dismissed as a gimmick, the band wins over the entire crowd, while the parents are impressed by their children's talent and confidence. However, No Vacancy wins, but the audience chants encore for the School of Rock, who perform for the crowd once again.
Sometime later, Dewey continues the School of Rock as an after-school program, coaching the students he played with before while Ned teaches beginners.