Audio problem: Near the end when the family have got back in the car Malcolm says something like "who would have thought a traffic jam could be so cool, we should do this again". Well near the end of the sentence we can see Malcolm's mouth and it isn't moving.

Continuity: When Lois and Kitty Kenarban (Stevie's mom) are at the table in the restaurant, while Hal and Abe sit at the bar, things on the table change position or disappear and reappear between shots. Same thing happens at Malcolm's table with Reese and Stevie.

Audio problem: When the girl Krelboyne is talking loudly, you can see her mouth barely matches anything she's saying.

Continuity: During one of Reese's cooking classes, Hal puts some bread into a toaster. It then cuts to a shot of Reese. When it cuts back to Hal, the toast that pops out of the toaster isn't the same shape as the bread he put in.

Continuity: When they are bowling, Malcolm decides to walk up the alley to make a strike. The shot behind him shows him walking into the lane. When the shot switches to the front, he's walking over the line again.

Continuity: When Francis gets pulled over, his window is open and closed between shots.

Visible crew/equipment: When Lois goes into labour with Malcolm, she runs outside taking Francis and Reese with her. When Francis says, "You're a liar, you're a liar," watch the back window of the car and you will see the camera and camera operator's reflection in the window.