Revealing mistake: When Cheech and Chong are parked in their car smoking a joint, the car is filled with smoke. The smoke must come from a smoke machine outside as it is moving around very fast as if blown by the wind. (00:13:25)
Revealing mistake: During the sax player's solo (final concert), his fingers don't match the notes, and he stops moving his fingers before the solo is over. Also, the sax player in the blue jacket behind Buddy's right side often lags behind the sax player to his right. At times, it looked like the sax player was watching the sax player next to him to know when to play. Sometimes, he would put the reed in his mouth for a fraction of a section and just pretend to be playing. Near the end, both sax players seem lost and even laughing at themselves. (01:47:17)