Other mistake: At the beginning of the film, Lorraine is in the bathroom while her sister is banging on the door outside. Notice how blonde her hair is as she is applying her lip gloss. At the breakfast table a few minutes later her hair is a different type of blonde. This is because Hilary Duff wasn't available at the time of filming the beginning of the movie and her bathroom sequence had to be filmed many months after the filming for the rest of the film had been completed.
Other mistake: When Steve Martin is seated at the table trying to find a babysitter, there are several quick shots of the phone book as he crosses out numbers, turns the page, etc. The very last shot of the phone book is backwards! While its easy to see the phone book, if you zoom in on the shot, you can clearly see that the tiles, words and letters on the board partially obscured by the phone book are backwards too.
Continuity mistake: When the kids are about to put Hank's underwear in the meat bucket, Henry and Jake insert cotton-ball type things in their noses. After they do this, we see that there is still a good amount of white sticking out, but in the very next shot, there is barely any white showing.
Continuity mistake: At school Mike Baker knocks the latte out of the bullys hand, and the latte falls to the floor spilling a bit of drink on the bullys shoe. Yet in the next wideshot of Mike lunging at the bullys legs, the drink cup has vanished and both of the bullys shoes are clean.
Continuity mistake: At the beginning of the movie, Steve Martin comes into their bedroom after a jog where his wife is proofing her manuscript. There's a pinwheel type of decoration attached to the lamp on top of some family photos in the corner by the window. In the 1st shots, you can even see its shadow on the lamp. Steve says (to Bonnie Hunt) "We could use a little change around here - like this lumpy old mattress." He then moves to the mattress facing her and the photos are still there but the pinwheel thingy is gone.
Continuity mistake: In the kitchen when Kyle and Nigel run to their dad, Tom, and start yelling and doing macho actions, in a wideshot you see Charlie walk from the stove, over to the worktop where Henry, Kim and Jessica are making sandwiches and he puts something on a shelf. Then in the following closeup of Nigel and Kyle you can see in the background that he has instantly vanished.
Continuity mistake: This takes place in the scene were Charlie Baker and Tom Baker are talking about Charlie missing his curfew: when Tom wakes Charlie up, notice how he is not covered up in his blanket, but in the next shot, you can see that it is over his legs, that would not be possible seeing as how Charlie was just then waking up.
Continuity mistake: When Hank is being attacked by the dog and the family is looking on and laughing, it cuts to Charlie laughing and he is holding a glass to take a drink, then it cuts back to Hank, and just a second later it cuts back to the family at the table and Charlie is sitting with his arm across his chair facing a completely different way, with nothing in his hands. There is no way he could have put down his glass and turned to lean back with his arm across the chair in that short of time.
Continuity mistake: After the scene where the kids get grounded, there is a scene of Mark laying in bed. He then rolls over in bed and stares at a picture of him and his mum. In front of the picture are his glasses, but in the very first overhead shot of Mark laying in bed, the glasses weren't in front of the picture.
Continuity mistake: When Tom is being interviewed on TV, it cuts to Lorraine who says "At least we get to see him on TV" and she has both her legs bent up in front of her. In the following wideshot of the 8 kids and Kate on the bed, Lorraine only has one leg bent up in front of her.
Continuity mistake: When the chandelier breaks and Tom falls whilst holding it, between shots the chandeliers lights go from being pretty much intact, to being totally smashed - and this is after the fall, so there is no reason for them to smash any more. The long yellow rope that attachs the chandelier to the ceiling changes the position it lays between the closeup of Tom landing (obviously not Steve Martin) and the following wideshot too.
Continuity mistake: When Steve Martin is talking to Bonnie Hunt about being gone for three days, watch the picture on the table. It moves closer to the edge of the table in the subsequent shot. In the first shot it is not covering the ring on the edge of the table, in the next shot it is.
Continuity mistake: When Beans the frog has been caught, Tom gives Mark the net with the frog in and then Mark smashes all of the glass/ornaments on the shelf, by swinging the handle of the net into them. Look at the mess of glass/ornaments on the side, just after Mark smashes them. When we see the shelf again, the position of the smashed glass/ornaments on the side had changed greatly, and things have appeared/disappeared.
Other mistake: At the end of the movie, Steve Martin is walking through the field where, just minutes before, he coached his last game (he looks at the scoreboard and his wife tells their children that he went alone to the game). Well, that seems a very immaculate football field for one that just had a college game played on it.
Continuity mistake: When Nora phones the Bakers, and she is on speakerphone, in the background you can see some various blue and green glass ornaments on the red wall-side, in the background of Hank playing his video game. These ornaments have moved along in the closeup of Hank frantically tapping his controller.
Continuity mistake: As Tom is about to go to work, Kate hands him a printout of Nora's email. Tom takes the paper and holds it at the bottom middle part. In the following closeup though, Tom is holding the left corner of the paper. When it cuts he is holding the bottom middle again.
Continuity mistake: When Hank is sitting on the couch, waiting for his clothes to dry, Nora comes in with lemonade. Tom and Kate start talking to Hank about his acting career and we see that Nora is holding her lemonade glass, but in the very next shot, the glass is on the table in front of her.
Continuity mistake: When Mark and Tom get off the train, Mark is wearing his hat. When the rest of the family come around the corner, he is not wearing his hat. We see it fall halfway out the pocket of his coat when he hugs Kate, but it seems he did not have enough time to take it off and put it in the pocket of his coat, especially given the fact he was using both hands to carry the box with his belongings inside.