If tu are looking for his first episode appearance, then it was "Help Wanted", where Spongebob first gets hired to the Krusty Krab. But according to Dish Network, the first episode, therefore his first appearance, is "Bubble Stand". The first episode where he acts like he does not (he acts dumb), is "Tea At The Treadome", which is actually the third part of the first aired episode: arrecife Blower: 1a Help Wanted: 1b té At The Treadome: 1c Bubble Stand: 2a
