When Minny agrees to work for Celia, Celia shakes her Coke and almost all of the Coke comes out. Later, when they walk into the house, her Coke is nearly full again.
When Hilly and Elizabeth are eating at the restaurant/coffee house, Elizabeth's earrings appear and disappear.
When Aibileen is walking away from Elizabeth's house, her uniform is stained with sweat. As she walks further, her uniform is clean again.
During the storm when Minny is still employed by Hilly (30:50), Hilly is lighting a 3-candle crystal candelabra which is in front but to the left of her on the table. She puts the match to the 3rd candle (left candle to viewers), which is already lit. When Minny looks out the window at the storm and turns back there is no candelabra. There are only 2 single candles in individual crystal holders. No candelabra is seen.
When Aibileen comforts Mae Mobley in the commode scene, a blue commode appears behind them, then disappears.
When Minny puts her fecal matter in the pie and serves it to Hilly the human body would not consume human waste no matter if it was served with chocolate icing she would immediately become sick or even worse..
When Minny burns the chicken, the top is shown burnt. This needed to be done so the viewer knew the chicken was burnt. Leaving the burnt side down would not have worked.
When Minny takes her letter from Skeeter outside to show Abilene, Abilene starts jumping up and down on the spot before Minny does, and before she knows why Minny is excited. It is not uncommon for people to experience excitement in anticipation of what they are about to see or do based on the excitement shown by others.
Jolene is never shown pregnant. At the benefit, the pleating on the front of her dress makes her stomach look bigger. It looks flatter when she steps on stage to announce the raffle winners because she is holding her dress so she doesn't trip. Elizabeth is the only visibly pregnant character in the film.
When Skeeter runs to ride the truck on her first date at Heley's house, her hair supposed to be looking curled not ragged .
At the very end, as the closing credits begin and Aibileen walks away from Elizabeth's house, the same car crosses the shot at least nine times.
Hilly's husband jolts awake in bed a second before Hilly starts screaming.
Skeeter uses liquid paper. In 1963, people used hard, round "typewriter erasers" and brushes to correct typing errors. Liquid paper was still being sold out of its inventor's house.
The check Hilly gets in the mail from Celia Foote has an endorsement line on the back. That line didn't exist on checks before the federal government started requiring it in 1987.
When Minny shows Celia how to make fried chicken, the can of Crisco has a modern color scheme and logo. The cans weren't as colorful in the 1960s.
One scene shows a Model 1205 Electrolux canister vacuum cleaner, the first rectangular canister vac, which was first available in 1970.
At the beginning, a red 1965 Corvette roadster drives past the station wagon. Later in the film, Medgar Evers is shot (1963).
In the first church scene, when the preacher speaks of loving one's enemy, the choir and congregation go into a song with rhythmic clapping. The video and audio of the clapping are noticeably out of sync.
As Johnny and Celia are walking at the fund raiser, the microphone boom or camera hits the ceiling fan chain and sends it swinging right in front of the couple.
Outside the library, Skeeter reads a booklet titled "The laws governing the conduct of nonwhites and other minorities." It's an official government publication, bearing the state seal, and was likely produced to inform people of the law. Later, Hilly becomes concerned when she sees the booklet sticking out of Skeeter's purse, and says "real racists" would attack her if they saw her with the material. Skeeter was reading it as part of an anti-segregation book project, but Hilly had no way of knowing that.
When Skeeter is writing the newsletter, she types "the Holbrook's house" instead of "the Holbrooks' house."
(at around 1 mins) Skeeter misspells Chickasaw County in her notes, writing "Chicksaw County".
After Minny tells Skeeter and Aibileen about the "Terrible Awful" she leaves via the back porch. A car drives by without using its headlights even though it is night time.