Character mistake: Throughout the entire series, the Turtles are referred to, by others and by themselves, as amphibians. But turtles are reptiles, not amphibians. However they are amphibious, amphibious reptiles.
Audio problem: When Donatello tries to stop April from leaving the sewers after she accuses them of committing the robberies, he is speaking in Raphael's voice. (00:10:35)
Deliberate mistake: When the turtles and April escape the building filling up with water, the shot where the hall is filling up with water is used twice.
Revealing mistake: When Donnie is fighting some foot clan solders, his belt has an M on it for a frame.
Revealing mistake: When the channel 6 crew member is telling April they should go, his hand disappears for a frame.
Continuity mistake: When Bebop's gun is sliced, Raph comes in from the left to knock him out. When he's down, Raph disappears.
Continuity mistake: When Leonardo slices Bebop's gun, he's wearing red.
Hot-Rodding Teenagers from Dimension X - S1-E4
Other mistake: General Traag's weather weapon causes a blizzard across the city, yet when the Turtles and the Neutrinos come up to the surface after the blizzard had been occurring for a while, none of the cars parked on the street, including the Neutrinos' two flying convertibles, are covered in snow. The interior of their cars should have been full of snow.
Invasion of the Punk Frogs - S2-E8
Plot hole: Shredder meets the frogs for the first time and gives them clothes using the holographic projector. The frogs continue to wear the same clothes for the rest of the episode, even without Shredder being around.
Continuity mistake: The turtle van falls on a bridge, the turtles escape swimming. Shortly afterwards, April appears driving the van, looking for the turtles.
Other mistake: The turtles are racing to save April, who is kidnapped by Shredder, and trying to get to the roof. They run into a squad of the royal guards and one of the guards shouts: "Halt! Hands in the air or we'll open fire!" Now, I would like to see that because every one of the guards is holding a sword. (00:14:00)
20,000 Leaks Under the City - S3-E14
Continuity mistake: The Octopus grabs Rocksteady, in the next shot on the boat, Bebop disappears and Rocksteady is on the boat.
Michelangelo's Birthday - S3-E31
Factual error: The very beginning of the episode shows Michelangelo's Birthday circled on the calendar, and it is shown as the second Tuesday of the month as well as being the 13th day. The second Tuesday of a month can never be the 13th. The earliest the 13th of a month can be is the second Thursday.
Suggested correction: This is simply wrong. If a month starts on a Thursday, the first Tuesday will be the 6th, and the second will be the 13th.
Slash: The Evil Turtle from Dimension X - S4-E33
Continuity mistake: Pizzas keep reappearing on the counter as Slash eats them.
Adventures in Turtle-Sitting - S6-E4
Revealing mistake: When Leonardo throws his katana at the tree which Michelangelo and April are tied around, you can see the rope is cut and begins falling off the tree before the katana touches it. (00:20:33)
Continuity mistake: Shredder's hand blades temporarily disappear when he's talking to Krang in the Technodrome.
