SpongeBob SquarePants
Eek, An Urchin! / Squid's Defense
S9 E5:
SpongeBob finds a nasty sea urchin living in the Krusty Krab in 'Eek, An Urchin!', and then in 'Squid's Defense', Squidward convinces SpongeBob and Sandy to teach him karate.