NICHIJOU - MY ORDINARY LIFE: EPISODE 0

While the title suggests a story of simple, everyday school life, the contents are more the opposite. The setting is a strange school where you may see the principal wrestle a deer or a robot's arm hide a rollcake. However there are still normal stories, like making a card castle or taking a test you didn't study for. — Description from AniList community (anilist.co).