Continuity mistake: Moose is sitting at a desk writing a letter to Mr. Dunbar in a spiral bound notebook. There is a magazine to the right of the notebook with about the same width. After a couple quick camera shifts, the notebook is suddenly stacked on top of a few magazines and whatever Moose is writing on is obstructed by the stack. After a couple more quick camera shifts, the notebook is back in front of Moose, and he tears out the page he was writing on. (00:25:55)
Continuity mistake: The lamp above the picture on the wall at the karate school/studio changes in appearance a few times. The first time Casey visited the school, the light bulb was covered by the lamp shade (which was aimed toward the picture); the bulb was not visible but it cast light onto the picture. When the picture was blurred behind Sensei, there was a round circle totally outside of the shade to represent the light bulb (which should have been inside the lamp shade and not visible). (00:15:30 - 00:27:17)
Continuity mistake: The spacing (almost touching versus several inches apart) and appearance (shape and whether there are shoots) of the two flowers in the vase on Estelle's/Betty's table at the restaurant vary. Sometimes, the flowers on her table look more like the ones that could be seen on the table in front of hers after Brian/Roy entered the restaurant. (00:03:40)
Continuity mistake: At the start of the film, a man is giving a tour of a building under reconstruction to some potential buyers. One shot, as he's telling them that this sits on a 14-acre lot, there are just 3 people as they walk through a doorway. The film jump cuts to a closer angle, and suddenly a 4th person appears in front of them from thin air. (00:02:34)
Continuity mistake: Mario was chewing a mouthful, then lifted his drink to wash down the food, but when the camera shifted, he was back to chewing a mouthful. (00:01:59)