The Snowball Effect / One Krabs Trash - S3-E3
Continuity mistake: In "The Snowball Effect" when Patrick tries to make a snowball the third thing he makes is a DNA strand, if you look closely, when it is in closer, the DNA strand is shorter than when they go out on it.
Mermaid Man and Barnacle Boy IV / Doing Time - S3-E1
Continuity mistake: At the start of MMIV, SpongeBob rips off a person's pocket to get a pen. He totally rips it off, but none of the pocket's material is visible later.
Goo Goo Gas/No Hat for Pat - S7-E9
Continuity mistake: In the episode where Plankton turns Krabs and the rest of the Krusty Krab into babies, baby Krabs is hitting Plankton with the secret formula while they are on the floor of the Krusty Krab. Krabs crawls away and Plankton picks up the bottle and declares how easy it was. The next shot he is suddenly on top of one of the tables instead of the floor.
Sandy's Rocket / Squeaky Boots - S1-E8
Continuity mistake: Sandy's Rocket: When you first see SpongeBob in bed you can see a mysterious glass window on the floor. When Patrick arrives it has vanished, evident in the wide shot.
Welcome to the Chum Bucket / Frankendoodle - S3-E2
Audio problem: The first time the man yells in "Frankendoodle", his mouth isn't in sync.
MuscleBob BuffPants / Squidward, the Unfriendly Ghost - S1-E11
Continuity mistake: When Squidward comes out of the bathroom and sees his melted sculpture, the eyes on the melted sculpture change from looking on the floor to looking up in a matter of seconds.
Continuity mistake: In some episodes, Spongebob can't even lift marshmallows on a stick (Ripped Pants). However in Texas, he somehow flips a guy coming up behind him.
Fear of a Krabby Patty/Shell of a Man - S4-E1
Continuity mistake: In the episode 'Shell of a Man", when SpongeBob pushes over Mr. Krabs' shell off of the chair at Mr. Krabs' desk, you can see that there are 2 eye holes, a nose hole, and a very large hole for the mouth. But when SpongeBob puts the shell on, both his nose and mouth are in the large mouth hole, and his eyes are in the eye holes. But there is no nose hole.
SpongeBob Meets the Strangler / Pranks a Lot - S3-E20
Continuity mistake: In Spongebob Meets The Strangler, the Tattletale Strangler's dots on his head change numbers constantly. Sometimes there are 5 on his right, sometimes 6, sometimes his left side has a scar and 5 dots, sometimes a scar and no dots.
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".
Grandma's Kisses / Squidville - S2-E9
Continuity mistake: In Squidville, when Spongebob and Patrick are using their reefblowers, Squidward changes from his dancing clothes into normal clothes in the next 2-4 shots when he is digging out of his house.
The Chaperone / Employee of the Month - S1-E12
Other mistake: When Pearl is crying in the Krusty Krab, the customers are just the same person over and over and over.
Continuity mistake: In "Suds" after Spongebob crashes through his bedroom window, the blanket is hanging over the side and is all wavy, but when he's in bed it's completely plain and doesn't hang over the sides.
The Great Snail Race / Mid-Life Crustacean - S3-E15
Continuity mistake: Gary crashes to a tire. After a while you see the tire is gone. Also, Gary stayed in the right of the track, crashed, but when SpongeBob helps him, Gary is in the middle of the track.
New Student Starfish / Clams - S3-E14
Continuity mistake: When Spongebob shows Patrick the good noodles chart all the stars are wildly scattered in each row. When Patrick is trying to announce his name to the class they're all in a neat row. When Mrs. Puff is removing the star from Spongebob's row they're scattered again.
Mermaid Man and Barnacle Boy III / Squirrel Jokes - S2-E4
Continuity mistake: When Patrick is struggling to carry a heavy box, he drops it a number of times on Man-ray's foot. The camera cuts away, then back to Patrick and Man-ray, and the box has disappeared.
Help Wanted / Reef Blowers / Tea at the Treedome - S1-E2
Continuity mistake: In "Reef Blowers," when Spongebob is flying back from the rope he is pulling, Squidward is nowhere to be seen. When the ocean is getting drained, Squidward is sitting on his porch.
Krab Borg / Rock-a-Bye Bivalve - S3-E8
Continuity mistake: In "Rock-a-Bye Bivalve," near the end, the timecard says it's midnight and it is dark outside. However, when the bivalve flies away, it's morning (judged by the shadows of the houses, even late morning), even though just a few minutes passed.
Valentine's Day / The Paper - S1-E16
Continuity mistake: In Valentine's Day, almost at the end, Patrick smashes some presents with his foot. After a while, Sandy arrives with Patrick's present (a chocolate globe), and you can see that the presents have disappeared.
Continuity mistake: When Spongebob is trying to get Squidward to write a letter outside, at the first shot of Spongebob, he's standing straight on the wood step thing, but the next shot he's facing to the side.
Answer: In the "Christmas Who?" episode's intro, Patchy the Pirate is reading a letter where a fan ask if Spongebob loves Christmas as much as he does. Patchy explains they didn't always celebrate Christmas and this episode is a flashback to the first time Bikini Bottom had heard of Christmas. Santa had never visited before because nobody had believed in him before. Santa finally does visit because of Squidward's Christmas spirit. The "It's a Spongebob Christmas" episode aired 12 years later. So by this time, Bikini Bottom had been celebrating Christmas for quite sometime. Santa comes for a special visit because of how everyone in town, except Plankton, is on his naughty list.
Bishop73