Pressure / The Smoking Peanut - S2-E12
Continuity mistake: When Sandy and SpongeBob are climbing the mountain at the beginning of "Pressure," when Sandy pushes the rocks down at SpongeBob, there were two big ones holding them that vanish. You could say that she pushed them down too, but remember that they were different colours than the smaller ones. (00:01:40)
Something Smells / Bossy Boots - S2-E1
Continuity mistake: When Pearl gives SpongeBob the new costume for the Krusty Krab, she gives SpongeBob a mirror. In the mirror, Squidward appears and tells him not to accept the costume. If you notice, Squidward is at the LEFT of SpongeBob. Because is a mirror, in the real life he would be at the RIGHT of SpongeBob. When a shot is shown of SpongeBob and Squidward, you can see that Squidward isn't at the RIGHT of SpongeBob, he's at the LEFT.
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.
Mermaid Man and Barnacle Boy III / Squirrel Jokes - S2-E4
Continuity mistake: In "Squirrel Jokes", right when he comes out of the curtains people put their hands up, but in a front view their hands are down.
Sandy, SpongeBob and the Worm / Squid on Strike - S2-E18
Continuity mistake: In "Sandy, Spongebob, and the Worm," the worm is about twice the height of Sandy and Spongebob. Near the end of the episode, the Worm charges off of the cliff and when he reaches the bottom, and smashes the town, the buildings are tiny compared to him and the sea creatures are microscopic.
Something Smells / Bossy Boots - S2-E1
Continuity mistake: When Spongebob is outside, and he takes out his "to do list" at first he is holding it with his right hand, but when it shows the front of the paper, you see that it is his left hand. Then it is his right hand again.
No Free Rides / I'm Your Biggest Fanatic - S2-E10
Continuity mistake: After SpongeBob sees the "Queen Jellyfish" (really Kevin the sea-cucumber and his friends) he drops his jellyfish call out of his mouth. When it cuts to a wide shot, the jellyfish caller is nowhere to be seen.
Big Pink Loser / Bubble Buddy - S2-E3
Continuity mistake: It seems to me that half the cards that Spongebob used for the card snail have disappeared when Patrick comes in.
You Wish ('Shanghaied') / Gary Takes A Bath - S2-E11
Continuity mistake: After Squidward comments about how the ship is dirty, he continues to climb up the anchor rope. Once he's out of the shot, the rope immediately changes color.
Mermaid Man and Barnacle Boy III / Squirrel Jokes - S2-E4
Continuity mistake: In "Squirrel Jokes", when Spongebob tells the joke about Squirrel in the second act she's at a table alone, but in the next wider shot there's a chair next to her.
Your Shoe's Untied / Squid's Day Off - S2-E2
Continuity mistake: In Your Shoe's Untied, when Spongebob takes the patty to Squidward, it's just a patty with lettuce, but in one shot, you can see cheese and pickles on it.
Continuity mistake: In the morning when they all wonder where Santa is, and Spongebob keeps singing "Santa's coming tonight", once everybody walks away, Patrick appears right next to Spongebob.
Your Shoe's Untied / Squid's Day Off - S2-E2
Continuity mistake: In Squid's Day Off, when all of the coins go out of the cash register, you see 14 coins drop. When Squidward picks up the coins, there are only 12.
The Bully / Just One Bite - S2-E17
Continuity mistake: In "The Bully" SpongeBob accidentally runs into Flats' dad's car and there is only one seat. Later Flats is shown sitting in the car.
Pre-Hibernation Week / Life of Crime - S2-E13
Continuity mistake: When Spongebob has melted from stress and exhaustion, he is trying to talk and Sandy tells him to "hold that thought", and you can see the bike that they were riding, in the background. When she makes the fly fishing joke, the bike is gone, and there is a small plane. A few shots later the plane is gone as well.
Mermaid Man and Barnacle Boy III / Squirrel Jokes - S2-E4
Continuity mistake: In "Squirrel Jokes", at the beginning of Spongebob's 2nd act when he's at his mirror backstage, a random object appears on the table.
No Free Rides / I'm Your Biggest Fanatic - S2-E10
Continuity mistake: In "No Free Rides", after SpongeBob puts his socks on the boat he goes in the boat and falls asleep, yet when he is being dragged by the boat he has his socks back on.
You Wish ('Shanghaied') / Gary Takes A Bath - S2-E11
Continuity mistake: When Gary goes through the pet door to run away from SpongeBob, when SpongeBob opens the door, there is no other side to the pet door.
The Bully / Just One Bite - S2-E17
Continuity mistake: When Flats moves out of the way we can see his pictures on the blackboard. The camera cuts away from him and back. The pictures are then taking up much more of the board than before (they go over the top of his head).
Big Pink Loser / Bubble Buddy - S2-E3
Continuity mistake: When Patrick in Spongebob clothing is first revealed (when the rock is raised), Patrick has no collar, yet in other shots the shirt has a collar.
Answer: I believe this is the Season 6 episode "Spongicus".