Continuity mistake: When Max and the evil ice cream man are fighting at the Chinese place, Max has very few, if any papers with him, then the next shot of him riding down the street he has a lot more papers in his bag.
Continuity mistake: When the ice cream man and the kid in the suit and tie are fighting, in one angle, the kid's tie is thrown over his shoulder and in the next view it is back down. In the next shot it is back up over his shoulder again.
Continuity mistake: When Max walks out of the assembly room with trash all over him, Robe grabs a single noodle from Max's ear. In the next shot we see that Robe has many noodles wrapped around his fingers.
Continuity mistake: When the principal throws the football at the secretary, it knocks down all the flowers. The scene cuts to the principal and back to the secretary. The flowers are back up.
Continuity mistake: When Max's friend falls on the bus, she drops her instrument and the top of the instrument can be seen poking out of the case. However when she gets up the instrument is fully covered.