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Bonky Fever - S4-E30
Continuity mistake: When the gang arrives at Mikey's house with his birthday gifts, note the colours of the gifts that Gretchen and Gus are holding. When the gang looks at Spinelli's gift, Gretchen and Gus's gifts have swapped colours, then they swap back in the next shot.
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Bonky Fever - S4-E30
Continuity mistake: In the cafeteria, Mikey asks the lunch lady for more pudding for Bonky. When the lunch lady refuses, the clothing on Mikey's Bonky puppet has vanished, then it reappears in the next shot.
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Bonky Fever - S4-E30
Continuity mistake: After the gang gives Mikey his backpack full of Bonky stuff, Mikey runs away from them, and he is heading towards two kids playing marbles. Then, when Mikey slips on the marbles, they have changed colour.
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Bonky Fever - S4-E30
Continuity mistake: After the gang finds out that Mikey was sucking on a Bonky pop, they find his backpack, which is its usual green colour. Then, when they discover all of the Bonky stuff inside it, it has changed to red.
Bonky Fever - S4-E30
Continuity mistake: When the gang talks about Mikey's birthday party near the start, Gretchen's bicycle helmet constantly changes throughout the following shots. First, part of her helmet changes from purple to blue, then it's purple again and the straps vanish, then they reappear, then the helmet becomes red, then it's the correct colours again and the straps become blue, and finally, the straps change back to purple mid-shot.
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Other mistake: When the Ashleys are first shown playing jacks, Ashley T's nose seems to be missing; then it reappears three shots later.
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Schoolworld - S4-E21
Continuity mistake: The door to Miss Grotke's classroom opens inward throughout the episode. However, when SAL mimics Principal Prickly and tells all the teachers to report to his office, Miss Grotke leaves the classroom, and the door now opens outward. Then, when the kids look outside the classroom, the door has completely vanished.
Schoolworld - S4-E21
Continuity mistake: When Gus gets locked out of the school after recess, he asks SAL to open the hallway door. He looks up at the clock, and the time on it is 10.46.05 (then goes up to 10.46.08 by the end of the shot). A few seconds later, the time changes to 18.46.16, then 10.46.17, then 10.45.18.
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Continuity mistake: When Randall begs Gretchen to do his homework, Mikey says, "Tutoring is just another word for helping," and his backpack is green. A few seconds later, it changes to blue.
The Biggest Trouble Ever - S4-E13
Other mistake: When the court hearing is taking place, T.J. wears a tie with blue and red stripes. As T.J. says to the mayor, "Sorry, sir, may I say something?", the stripes on his tie change to the opposite color for one frame (not counting the stripes on the knot).
Continuity mistake: When the marble gets knocked out of Spinelli's hands and it falls into the drain, the marble approaches the hole to the very left of the drain, but in the next shot, it falls into the hole right next to it.
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Other mistake: When the Ashleys are playing jacks, Ashley B is wearing her usual yellow sweater, but in the next shot, it becomes red, the wrong colour. It goes back to yellow in the next shot.
Spinelli's Masterpiece - S4-E27
Continuity mistake: When the kids are all on the jungle gym to see Spinelli's drawing, Jerome can be seen sitting on the bar of the swings. However, when everyone is cheering he has suddenly moved to the ladder.
Here Comes Mr. Perfect - S4-E18
Continuity mistake: When Jared is holding his speech, Jerome's jumper turns blue twice.
The Secret Life of Grotke - S4-E32
Continuity mistake: When the gang are sat at the table before Miss Grotke comes on, the table is empty, but when Miss Grotke comes on stage, they suddenly have drinks.
The Spy Who Came In from the Playground - S4-E4
Other mistake: When the gang is showing stone their way into the school they go through a vent and all of them manage to squeeze through the small hole in the wall.
Chez Vince - S4-E41
Continuity mistake: In the cafeteria, TJ is wearing a suit to welcome the customers. But when he and the rest of the guys go to the teacher's lounge he's back in his normal clothes.
The Spy Who Came In from the Playground - S4-E4
Continuity mistake: After the part where Mikey gets double portions, the school clock shows it is half past one, but a couple of shots later shows the clock at half past ten, what kind of clock does that?
Continuity mistake: When Agents Barnes and Noble are passing out the test, there is a boy in a green hat sitting in front of a girl with long hair. The next shot is of the same boy asking if he can use a pen, but now there is another boy with blond hair right behind him.
The Spy Who Came In from the Playground - S4-E4
Continuity mistake: When the superintendent arrives at the school, he looks towards Stone who gives him a thumbs up. When he does this, Stone and the group around him are on the steps right in front of the entrance to the school. A couple of shots later, the entire group has suddenly appeared in front of the window without time for all of them to have moved.