At the first dinner with Lars and Bianca, the glass of milk Lars is drinking suddenly appears on the opposite side of his plate when he begins cutting Bianca's food.
In the bowling scene, when Margo hits the pins, they all fall down. When the shot is returned to her, two pins in the left hand corner are left standing. Then when the shot is return the third time, all the pins are gone again.
In the first scene in the doctor's office, Clarkson's wristwatch reads 10:35, but Schneider's reads 12:15.
When Lars is handed the flower after church, he has it in his
right hand just before turning around to see Margo. After turning to see Margo he quickly throws it away with his left hand.
When Mrs. Gruner tells Lars that Bianca would like to volunteer at the hospital, she mentions that the bald children would love Bianca. That would lead one to think they must be children with cancer. However, later when we see Bianca at the hospital, the children she is "reading" to aren't bald. There is a lady doing sign language in the corner, and she encourages the children to mimic a telephone sound. This implies that the children are deaf.
The version of the Talking Heads song "This Must Be The Place (Naive Melody)" played at the party was never released on vinyl. The version played in the film is a live version recorded for the Stop Making Sense album but only appears on a Special Edition CD released many years later.
At the beginning of the movie after Lars gives his blanket to Karin, she runs back into the house. As she gets close her foot is caught on a bit of snow that then tugs on a different patch showing that the snow in this scene is just set dressing.
At the party, when the host puts on a vinyl record, she drops the needle on the first track on the side. But the song that comes out of the speakers is "This Must Be The Place (Naive Melody), which is the last song on the Talking Heads album, "Speaking in Tongues." As the last track, it would appear closest to the center of the album, rather than at the outside edge where the needle is placed. In fact, it has never appeared as the lead-off track on any vinyl album.