I am not much into the Hollywood scene, and rarely watch movies. However, I greatly enjoyed the 2003 movie, The School of Rock, with Jack Black.
They performed a School of Rock Reunion Concert in 2013, with all of the original actors/musicians. They must have carefully auditioned kids who could actually play their instruments for the movie, instead of faking it, because in the reunion concert, they were rocking out--playing original songs from the movie without backup musicians.
I don't know what kind of musician Jack Black is, but he was really good in the movie.... At least he played the part well.....