Throughout the movie, Malcolm uses 2 different methods to transform his body into Big Momma. One is through the use of a body suit (made of a stuffed cloth material, which is used when Big Momma is wearing a dress) and the other one is through the extensive use of prosthetic makeup (for when Big Momma is showing more skin, at the spa and at the beach). In the beach scene, Malcolm is clearly using the prosthetics when Big Momma is in a one piece bathing suit as much skin is exposed. Big Momma then puts on a big sun dress to cover up (while still wearing the bathing suit and prosthetics). Moments later, she starts chasing Bishop down the beach to the pier. After Bishop jumps off the pier and Malcolm (now with his mask off) looks over the pier, you can see under the big sun dress on his right shoulder that he is wearing the fat suit, not the prosthetics. There was no opportunity for him to have switched from one to the other.
In the scene where big momma shows how to shake the butt inside the house, you see a close up-shot of one of the girls laughing and then hiding her face (behind her iPod?), and in the next scene she can be seen in the background with her hands down on her lap, nowhere near her face.
When Malcolm is looking at the photos of the blonde surfer, the photos change position on the table between shots.
Malcolm knocks the heater over at the safety convention, yet it's upright in the next shot, then knocked over again.
In the scene where Big Momma is pouring milk into a box of Lucky Charms for Carrie you see that after she pours in the milk, she places the milk bottle down upright, but in the next scene the milk bottle is on its side face down and crushed, yet again in the next scene it's upright and normal again.
When Big Momma is in front of the Hasidic synagogue, most of the men are all wearing large prayer shawls. In fact, the large shawl is used only during the daytime. The men would only have been wearing small ones.
When Andrew jumps off the bunk bed onto the mat of alphabet letters, the letter "S" is missing.
At the end of the movie, Malcolm is shown taking the newly born baby out of a forward facing car seat. Babies are required to ride facing the rear until the age of 12 months.
The Fuller's dog is referred to as Poncho, a male Chihuahua. Yet, when all Carrie's fellow cheerleaders show up to the house to practice their routine, Poncho stands on his hind legs - and it's clearly a female Chihuahua.
Chapter 13; after the super models pass, Big Momma's left wrist is not only missing her watch but also you can see the edge of the body suit.Then on her way to her locker she has a big gold watch on.
When Sherri, Malcolm's wife, is talking to her friend, showing her the large panties she found under her bed, the sides of the underwear change from back to front with no sign of Sherri making the change.
The washing machine was violently moving, while load of laundry was clearly balanced.
When Big Momma is confronted by the lady wanting to fight her at the bingo game, you can see Carrie turn to her and mouth the word, "Big Momma" though you can't hear her. Then there is a close up on her saying, "Big Momma, do you even know this lady?"