Cleanup! Titan Junior High School

Seisō! Kyojin Chūgakkō (清掃！巨人中学校) is the 4th episode of the 1st season and the 4th episode overall of the Attack on Titan: Junior High anime, produced by Production I.G.

Overview
Eren and the gang are forced to join the Wall Cleanup Club since the Scout Regiment is an unapproved club. There, they are tasked with cleaning windows by Rico. Impressed by their work, she agrees to teach them how to use the club's secret equipment, the vertical maneuvering gear. Eren, however fails the test because of an equipment failure. Hannes, the club's advisor, arrives to show him how it is done, but crashes into the wall due to being drunk. This allows Rico to save face by blaming the broken equipment on Hannes. Two Titans then appear, and as the club watches in horror, as they graffiti the wall. Rico explains that this is why the Wall Cleanup Club was originally founded. Outraged, Eren attacks the Titans, only to end up covered in paint.