Continuity mistake: During the other father's song, notice the red record player by the door and the position it's in, with the lid facing Coraline when he says, "making up a song". When the camera angle changes and he says, "she's a doll", the record player's position changes completely, with the lid now facing the wall.
Continuity mistake: During Coraline's first meal with her Other Mother and Father, just before Coraline says "I'm real thirsty." there are two drinking glasses to her right, the one she uses a couple seconds later and a smaller one. After the cut to the chandelier lowering, it goes back to Coraline and the smaller glass has completely vanished.
Continuity mistake: When Coraline goes to see her father for the first time in his study, there are three boxes at the entrance. She enters, puts the Coraline doll down on the smallest box with the doll's legs and right arm hanging down, then she starts playing with the creaky door. When her father tells her to stop, the boxes have changed position and the doll's legs and arm are straight.
Continuity mistake: When Coraline first finds the door, we see her mother on her computer, with the "I Love Mulch" mug's handle facing the doorway so we can see the words. However, in the next shot of the mother, while the camera angle has changed, the mug has rotated itself and the words are still visible.
Continuity mistake: When Coraline and Wybie are flipped around Mr. Bobinsky's door on the way to the mouse circus, you can see that first they are on the outside of the door, then when they are in the house, it is the inside of the door. If they flipped on the door that way, they would stay on the same side of the door, not switch sides. You can tell by the curtain rod, you can see the ends of the rods where they are mounted only when they are in the house.