Continuity mistake: Takumi and Shingo both have their right hands duct taped to the steering wheel, as per the rules of the Gum Tape Deathmatch. During one shot of the race, Tak's hand is no longer taped and resting casually on top of the steering wheel as opposed to the right side of it.
Doug Takes a Hike / Doug Rocks - S1-E4
Continuity mistake: When Roger is dancing in Skeeter's yard, he changes color.
The End of Flutter Valley (3) - S1-E3
Continuity mistake: When Reeka is conjuring the fake rainbow to distract the Flutter Ponies, the grey pot on her head is blue for a while.
Bat Mitzvah Crashers/Super Secret Weakness - S1-E5
Continuity mistake: In "Li'l Orphan Happy" when Ben makes his mom the tuna salad, it has lettuce around it, but in the close-up the lettuce disappears. When it gets zoomed-out on, the lettuce is back.
Continuity mistake: Towards the end of the episode, Phil walks out the bathroom in a homemade turban, imitating Chuckie's role of "Chongo" Nicole's hair has turned black at this part, in place of it's usual brown.
Mainstream - S3-E3
Continuity mistake: When Kitty goes to get a midnight snack, her hair is down. But a few shots later, her hair is up in a ponytail.
Heads Of Beef / Klub Katz - S1-E11
Continuity mistake: In "Klub Katz" Courage spins his head once or twice. But when he puts his head back on it spins way over once or twice. (Like a thousand)
Continuity mistake: After their victory, the Turtles are celebrating and partying. Just before the episode ends, Leonardo is dancing on a white mat and doing the moon walk. It cuts to a higher angle and suddenly the white mat vanishes.
Continuity mistake: Fluttershy's neck disappears after she says, "I don't know if I can cheer enough to help her".
Unicorn Club/Go Gomez! Go! - S1-E2
Continuity mistake: When the cats are entering the race the height of the sign lowers when Waffle walks up.
Continuity mistake: The broken glass on Nathan's face and arms disappears when he is pouring out the rice, but reappears when he is yelling into the PA system.
Continuity mistake: Just after Otis makes the ghost sounds from inside the house, it shows the gang standing together outside the house. Otis is with them outside, which is impossible, as he is inside the house pretending to be the ghost.
Continuity mistake: When Jimmy is in his lab, in the shot where the camera zooms into his eye, in the shot just before that shot, notice the digital clock on Jimmy's counter. The seconds part jumps from the 30's to the 40's twice in two different shots.
Fiend is Like Friend Without the 'R' - S1-E4
Continuity mistake: Mandy hits a baseball with one of Grim's bones, yet when we see Grim, there are none of his bones missing from his body.
The Secret Of The Juice - S1-E10
Continuity mistake: When Tummi goes looking for Zummi, Gruffi and Cubbi, he arrives right outside the barrel room. When first seen, the barrel room door is smooth, but in the next close-up the door suddenly has an iron grill window in its surface.
Continuity mistake: In the scene where Thugnificent is giving Riley is new chain and holds a speech, we can see that Riley's chain is as long as Thugnificent's. However, when he actually hands it over to Riley and when Riley does wear it, the chain is considerably shorter to compensate for Riley's length. (00:10:10)
Half-Baked - S2-E2
Continuity mistake: There are three boxes of cupcakes stacked on the coffee table. However when Trixie picks them up, as the shot changes there are now five boxes of cupcakes. (00:12:10)
Happy Birthday, Kevin (or Happy Birthday, Douchebag) - S1-E12
Continuity mistake: After Carlos sees the snake on the pole he leaps off the roof onto the pole. When he jumps you can see it's quite a distance from the roof. After catching the snake he is holding onto the pole and asks to be helped back onto the roof. The other characters just put their hands out and pull him up. There was no way with the distance between the pole and the roof they could have come close to reaching him the way they did.
Continuity mistake: In the scene where Mr. H. Makes Bloo wash his hands, Mr. H takes off his gloves and washes his hands then dries them. Notice that as soon as he takes his hands out from underneath the towel his gloves are back on.
Continuity mistake: When Lin lifts the rocks around the house in the final scene, there are eleven of them. But in the last shot, there are only eight rocks.