(at around 18 mins) When Nancy and Quentin are talking in the school, between shots Quentin's jumper moves so that 'Joy Division' is fully visible on his T-shirt, however when the camera moves back to the position it was before, the jumper has moved back, so that you can only see 'Y Divis'.
(at around 25 mins) When Jesse tries to comfort Kris before they get in bed, he puts both hands on the sides of her face. In shots from Jesse's point of view only his right hand is on her face, while from Kris's point of view both hands are there.
(at around 16 mins) The cardboard boxes marked 1996 and 1997 in the attic rearrange themselves between shots.
(at around 30 mins) When Jesse runs out of Kris' room he grabs his pants and shoes. In the next scene when he runs out of the house he is wearing them without having taken the time to stop and put them on.
(at around 34 mins) When Quentin answers Nancy's phone call you can clearly see the main screen instead of the blue in-call sequence. Later he presses the phone closer against his face and the application screen appears.
At around 26 and a half minutes, soon after Kris leaves her house, the distinct shadows of the crew and the outline of a boom mic can both be seen against the walls of the house behind her.
(at around 1h 9 mins) Sign in front of gas station states they accept "LINK", the Illinois government assistance program, where the movie was filmed. "WIC" is the Ohio government assistance program, where the movie takes place.
Above Kris and her stewardess mom leaving for London as they say goodbye in the front doorway of their house.
(at around 35 mins) When Quentin is searching the internet, he types the search term "sleep deprivation" then presses enter, then uses the mouse to click the search button (blast off). Generally, after pressing enter, you wouldn't need to click the button afterwards to get the results.