Continuity mistake: Phoebe is going into the school in one scene, but as the camera moves she vanishes while on screen.
Parents Day - S5-E6
Continuity mistake: In the tricycle section of the last event, the chinpiece of Helga's helmet keeps switching colors.
It Girl / Deconstructing Arnold - S4-E9
Continuity mistake: When Eugene breaks into the area with the dogs, you see the pedals of his bike tossed into the air, but the pedals fell off on the other side of the street.
Career Day / Hey Harold! - S3-E11
Continuity mistake: There are more than 16 slips in the hat, but only 16 students in class, and only 12 hands went in to pull out slips.
Helga's Show / The Flood - S3-E15
Continuity mistake: Grandpa's rubber raft got much bigger between the time he left the greenhouse and the time he arrived.
Big Gino / Jamie O. In Love - S4-E2
Continuity mistake: During "Jamie O. in Love," in the very last scene, Jamie drives up in a car whose front license plate reads "Killer." When they leave, the back license plate reads "Killr." There is no space for a letter to have possibly fallen out (not that a letter can fall off of a license plate).
Steely Phil / Quantity Time - S2-E12
Continuity mistake: Chinese Checkers is supposed to be with ten pieces per side, not six.
Freeze Frame / Phoebe Cheats - S2-E8
Continuity mistake: The next night, Phoebe's bed clothes switch back and forth between her nightgown and her dress.
Casa Paradiso / Gerald's Tonsils - S3-E3
Continuity mistake: Gerald's doctor's name is spelled "Murray Stieglitz" on the sign, but "Steiglitz" in the credits.
Bag of Money / Principal Simmons - S5-E4
Continuity mistake: Iggy removes his sunglasses - twice.
Suggested correction: The first time he is holding his glasses there was time for him to remove them we just did not see it. The second time we see him remove them.
Runaway Float / Partners - S2-E20
Continuity mistake: Runaway Float: When Arnold first sees the beeper float, he says, "How can they control that thing?", and Gerald is sitting on the curb to the right of Arnold. In the next shot, Gerald is suddenly behind him. Arnold is also a lot further away from the curb than he originally was. (00:08:16)
Love and Cheese / Weighing Harold - S4-E7
Continuity mistake: Lila was pretty much entirely underwater in a "standing" position when Arnold rescued her, how come suddenly the water only reached her knees?
Arnold's Room / Helga vs. Big Patty - S3-E4
Continuity mistake: In the locker room, Sid's hair goes from stringy to full and back to stringy.
Eating Contest / Rhonda's Glasses - S2-E13
Continuity mistake: In the last scene, Rhonda is seen through the bus's rear window as sitting in the back of the bus - but just before that, she's talking to the girl with the frizzy hair in a seat closer to the front.
