Oh, Teacher! (1927) - Oswald the Lucky Rabbit Theatrical Cartoon Series

Oswald the Lucky Rabbit enthusiastically sets out for school on his bicycle, stopping along the way to pick up his girlfriend. On the way, the young lady is accidentally dumped into a lake. She calls "help"; Oswald seizes the word itself out of the air and rides it to her aid like a bicycle. While trying to pull the girl out of the water, one of his classmates (a big cat) uses Oswald's back as a pontoon bridge and rescues her himself. Humiliated, Oswald decides to pick a fight with the cat in order to impress the girl rabbit. The cat responds by knocking Oswald's head clean off his shoulders. Recovering nicely by recess, Oswald lays in wait for the cat, armed with a brick, after detaching and kissing his own foot (he is a lucky rabbit, after all). Caught by the cat red-handed, Oswald throws the brick in the air in his haste to surrender. It lands on the schoolhouse roof, falls into the drainpipe, and knocks the cat out cold when it emerges from the other end. Oswald takes credit for the KO, and the girl is suitably impressed.

(copied from ThrottleBox: You can download this entire cartoon there)