School of Rock (2003)

Jack Black plays a guitarist who gets kicked out of a band because he grandstands too much – or, to put it another way, enjoys himself. Through an intercepted phone call, he gets a job as a substitute teacher for fifth grade at a private school. Neither students nor teacher quite know what to do with each other until Finn discovers that some of his young charges can play instruments; at once he starts turning them into a great rock & roll troupe that can crush his former band at an upcoming competition.