Sandy, SpongeBob and the Worm / Squid on Strike - S2-E18
Continuity mistake: When Spongebob shows Sandy the paper clip and a piece of string the string is very small. Yet later after Sandy says, "no silly, how about s for saving our skins", the string is a lot longer.
Procrastination / I'm With Stupid - S2-E19
Continuity mistake: In "Procrastination" when Spongebob is moving back and forth on his chair while writing his essay there is no pencil on the desk, but when he goes back to work on the essay there is.
Suggested correction: The pencil is sitting to the right of the paper the entire time. It's hard to notice at first, but it's there.
Procrastination / I'm With Stupid - S2-E19
Continuity mistake: When Janet and Marty (Patrick's fake parents) let go of Patrick's hands in the living room, Marty is on the left. But when Janet and himself pat Patrick, his hand is to the right of Patrick.
Procrastination / I'm With Stupid - S2-E19
Continuity mistake: The essay is titled "What not to do at a stoplight", then later when that same essay is seen again now the title reads, "What not to do at a spotlight".
Procrastination / I'm With Stupid - S2-E19
Continuity mistake: In 'Procrastination' when SpongeBob takes the stack of paper out of the drawer, the paper is the only thing in the drawer. In the next shot, SpongeBob pulls a pencil out of the drawer.
Procrastination / I'm With Stupid - S2-E19
Continuity mistake: Procrastination: When Gary eats all the food, he burps out his bowl. A ladder suddenly appears next to it.