Four Score and Seven Migraines Ago - S1-E86
Continuity mistake: After reminding Lincoln of his address on Pennsylvania Avenue, Wakko, Yakko and Dot simultaneously change positions between shots, moving closer to a table on the train cabin floor.
Goodfeathers: The Beginning - S1-E20
Continuity mistake: When Bobby and Pesto first meet Squit they begin to mock him. In the background a nearby trash can disappears from the sidewalk.
Continuity mistake: During the road trip to Fort Knox, Brain uses a system of pulleys to operate the minivan's steering wheel. After passing a truck stop, Brain becomes drowsy and in the next shot is seen holding the left pulley handle differently.
Continuity mistake: When Pinky and Brain are sneaking out of Acme Labs to commandeer the red minivan, Pinky's spoon and brown sack both disappear between shots.
Continuity mistake: Towards the end after Dr. Scratchansniff backs his car out into the road, Yakko tells him about next weekend's date. Then, in between shots, the car parks itself on the sidewalk.
Continuity mistake: When Dr. Scratchansniff storms out from his car and starts bickering with the jockey in a pink convertible nearby, the white painted lines leading up to the Snackaterium space themselves out considerably after a couple of shots.
Continuity mistake: In the stable where Pinky and Brain are searching for the Kentucky Derby's winning horse, Phar Fignewton's name tag changes its appearance within a couple of shots. Initially the name is written together, but a few seconds later Phar and Fignewton are on separate lines.
Continuity mistake: Inside the Hotel Bomb Adventure's restaurant where Skippy pounds a chicken drumstick with another drumstick, the one he's holding vanishes from his hand between shots. Also, the drumstick on the table in front of him suddenly jumps onto a plate.
Continuity mistake: Pinky instantly jumps to different positions between shots while standing on the magnetic infindibulator blueprint, right before Brain starts outlining the plan.
Continuity mistake: Throughout the episode, Flaxseed's candy shop door changes design. Sometimes it has no windows or knobs, depending on the shot.
Continuity mistake: After opening his cookie, Yakko holds the fortune with both hands. But when the shot changes he's only using his left hand.
Continuity mistake: In the scene where Wakko constructs a barricade of doors in the secretary's office just to keep Yakko and Dot from busting in to answer the phone, Yakko decides to paint a door of his own, on the adjacent wall. But the couch and mirror, which were there only a few shots ago before he started painting, have disappeared.
Continuity mistake: After Yakko, Wakko and Dot jump out from their wooden crate and start tearing books from the shelves, the alphabet briefly disappears from its place above the chalkboard.
Four Score and Seven Migraines Ago - S1-E82
Continuity mistake: Yakko and Dot switch places with each other between shots after they've started tossing around ideas for the opening of Lincoln's Gettysburg Address.
Continuity mistake: As Mr. Plotz tells the Warners to get out of his life, Yakko's left hand keeps changing its position on Wakko's shoulder with each shot, right before the office phone rings.
Continuity mistake: When Dot is about to sing for Beethoven on top of the piano, her microphone switches hands between shots.
Continuity mistake: When Mr. Plotz's secretary sneezes and sends her desk flying across the office floor, the telephone on top gets knocked from its hook and dangles over the edge. After she uses the intercom to call in sick we can see the phone hung up just like before, but her hands never touched it at any point.
The Three Muska-Warners - S1-E170
Continuity mistake: When the King of France is frightened by the Viper's arrival at 11:30, the digits on the grandfather clock's face change over to Roman numerals upon closeup.
Continuity mistake: When the Warners are at Pablo Picasso's home applying for modelling jobs, the front door hinges switch sides on the frame - immediately after Dot plants a few kisses on Picasso's cheek.
Continuity mistake: While watching Mr. Dan Anchorman on a control room monitor, Dot's hands jump to a different location as soon as the shot changes. At first she has both hands resting on the control board, then her chin.