Katekyo Hitman Reborn!

Nezu is a terrible teacher who makes fun of students who get bad grades. On the day he has to return his students’ science tests, he shows the entire class Tsuna's answer sheet, which has received poor marks. Gokudera is angered at Nezu for making fun of Tsuna and confronts him, but Tsuna and Yamamoto stop him from causing any physical harm. Nezu falls over and is angered; he blames Tsuna and his friends for his injuries. He says that they should be expelled. Thanks to Kyoko's pleading, Nezu will forgive them if they retake the science test and get good scores, but…