Revealing mistake: On Billy's first day of school when he is outside waiting for the bus and it just passes him you hear the noise of kids on a bus, but when it passes no one is in it.
Revealing mistake: When the car is falling off the cliff you can clearly see that there is 1 person in the car, it's not packed with the whole family like before.
Suggested correction: There's not actually any people in the car when it goes off the cliff. But the car is packed with multiple dummies to simulate the entire family.
Revealing mistake: When Eric gets mad at Max, chucks his stapler, and hits his secretary, the stapler is already on the floor when she gets hit. (01:04:45)