Continuity mistake: While at Dino Stop, Katie convinces her dad not to play it safe and to take a chance to save the world. Rick agrees and extends his left hand for the "all hands, Mitchell family on three." In the closeup we see Katie put in her right hand, but in the wide shot Katie's left hand pulls out. Also, note that in the closeup both Katie's and Aaron's positions between their parents are switched. (00:45:00)
Continuity mistake: When watching the water retreat after Sisu falls, a view from behind the characters shows Noi sitting on Tuk Tuk. The very next cut shows Tong picking her up from the ground. (01:18:01)
Revealing mistake: When Jake is sliding on the floor at the mall trying to grab his retainer, streak marks are visible on the floor from where they practised the shot.
Factual error: During the escape from the farmers market a red London bus is in the background. Those busses aren't used in Gloucester.
Revealing mistake: There's no doubt that Joey and his mother were not real kangaroos, but there wasn't even an attempt to make them look at least semi-real with animatronics or better CGI. The kangaroos' appearances were more along the line of what would be expected in a cartoon or all-animated movie. (00:01:00)
Continuity mistake: At the beginning of the movie, the real estate agent greets the McKenzies, lovers of all things open. The potential clients hold the papers in a completely different way at the cut ("I was just telling the Breckins that..." etc). (00:01:15)
Continuity mistake: The angle of the laptop on the kitchen table changed (and no-one was close enough to have moved it). The laptop was initially more evenly aligned with the edge of the (round) table. A little later, the laptop was not visible, but probably should have been. (00:04:09 - 00:04:44)
Revealing mistake: When "Snowball" is sleeping on Lena's bed, it is obviously a "stuffed double" (stand-in). Snowball is usually partially hidden behind the dog (so breathing doesn't need to be shown/mimicked). The failure of Snowball to make even a slight movement is a giveaway (e.g, no ear movement when Lena starts talking), but even the stuffed lion, in itself, is not a very good replica - it simply looks fake. (00:33:44 - 00:48:20)
Continuity mistake: When Tom knocks down the bike at the car, the position of the fallen clothes changes between shots.
Continuity mistake: While Porky is rapping, Al - G and Dom swap spots between shots.