Continuity mistake: During the scene where Gaby and John are in her bedroom talking, she takes a drag from her cigarette while John asks why she isn't happy, but never exhales the smoke from that drag. 23 seconds pass from that drag to the next one and she's in frame the entire time (it cuts between shots of the two of them together and Gaby's close-ups, but doesn't cut away from her). It's also worth noting that Gaby is never seen smoking again at any other point in the series and no explanation is given as to why.
Continuity mistake: About halfway through the series, Drake and Josh's door changes from facing the camera to facing the right (the other direction).
Raging Bull - S1-E6
Continuity mistake: When Phil has Myron pushed against the lockers and the sunglasses are on, one scene shows that they are not on his ear. In the next scene when they show Myron the sunglasses are placed perfectly on his ear.
On The Edge - S2-E9
Continuity mistake: When Al goes to the ship to get the explosive, his dingy is powered by a Seagull outboard. When he returns, its a Mariner.
Continuity mistake: When Cassie is in the headmaster's office, her red pencil case keeps changing position from being held up clutched to her chest with her folder, to being in her lap.
Continuity mistake: Season 1, Episode 5: "The Other Cousin." When Bleh enters her bus home, she receives 50 bucks from a retarded version of Spanky; there she wears her usual brown coat. But as she holds up the bill, she already wears the white fur coat she buys in the NEXT scene.
The Script and the Sherpa - S1-E5
Continuity mistake: When Vince and Eric are smoking weed with the older guy in the car, the older gentleman, Scott, is smoking from a joint less than an inch long, and proceeds to pass it to Eric. Eric, in turn, takes a hit and hands it to Vince, only the joint is now closer to two inches long.
Continuity mistake: When Dennis Leary and Michal J. Fox are at the bar, the shot Michael J. Fox has changes from being empty to partially full between shots, multiple times.
Continuity mistake: In the scene where Maria talks about wanting to throw the vase to the floor, the vase changes between shots. When she eventually throws it to the floor it's the original vase. This was most likely done due to a retake that had to be shot after the original vase was thrown to the floor and destroyed.
Continuity mistake: Bob Fossil records Howard saying "Gorilla" on his talk box, which Howard does with a downward inflection at the end of the word. However, every time Fossil plays back Howard's "Gorilla", it has an upwards inflection at the end of the word.
Continuity mistake: When Brian and Gerry are chasing Kelly, Kelly's jacket is only zipped up at the bottom at the start of the chase, but when the camera angle changes it is zipped all the way up for the rest of the chase.
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: Although this episode takes place during a single day, Boyce and Mac's hairstyles change from scene to scene.
Continuity mistake: When Shirley walks through the door you can see over Alan's shoulder that he's reading the comics in the daily paper. As they talk the paper changes to the business section.
Continuity mistake: In the cake song, Stingy puts in chocolate but never picks up the bowl. A few shots later, he is now holding the bowl.
Continuity mistake: Mr. Monroe (Jim J. Bullock) is explaining infant care to his class using a rubber doll when a paper airplane with a sense of direction starts buzzing his head. He swings the baby, hitting the skeleton next to his desk, shattering its head and sending it to the floor. In the next cut, the skeleton is standing up again, and Mr. Monroe whacks it down again.