‘School of Rock’ Teacher and Sonic Youth Member Jim O’Rourke Had to Teach Miranda Cosgrove How to Sing Poorly

School of Rock was destined to become a modern classic when it hit theaters 20 years ago. Between the cast, story, and soundtrack, the movie couldn’t lose. For many, the character Dewey Finn cemented Jack Black’s position as Hollywood’s top rocker.

However, a new history piece put together by Reverb, reveals that the unsung hero of the movie was really Jim O’Rourke, a celebrated record producer and former Sonic Youth guitarist.

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When School of Rock went into development, O’Rourke had just moved from Chicago to New York. Additionally, he had just joined Sonic Youth to take on guitar and bass duties. Randal Poster served as the film’s music supervisor and was friends with O’Rourke and his bandmate Lee Ranaldo. The team’s film brought the musician in as a consultant.

“They needed someone who could read and write music and could play in the traditional sense,” he told Reverb. O’Rourke, who had spent a decade as a guitar teacher said, “They didn’t just need a musician – they needed someone whole could teach music, and the things that go along with it.”

O’Rourke didn’t really have to teach the kids to play their instruments. Most of them were accomplished young musicians already. Instead, he taught the kids how to loosen up and rock. “Depending on where their musical background was coming from, I had to be able to teach or present from that position,” he recalled.

The music industry veteran didn’t just teach the kids how to rock. He tried his best to teach a young Miranda Cosgrove how to sing poorly. O’Rourke recalled that the studio wanted Cosgrove’s vocal abilities “toned down” for the role. “I remember we had two little school desks facing each other,” O’Rourke said, looking back on the lessons. “Mostly, I was trying to make her laugh, because she took it really seriously.”

However, O’Rourke’s involvement isn’t where the School of Rock and Sonic Youth connection ends. When they weren’t shooting the kids would join their teacher at Echo Canyon, the Sonic Youth-owned studio in Manhattan near where the World Trade Center used to be.

In short, School of Rock may have introduced a generation of moviegoers to killer classic rock, but it had experimental noise rock in its DNA.

Photo by Kevin Winter/Getty Images