Continuity mistake: When the family goes to throw Carla through the window, watch the window they throw her towards. The window is made up of at least three sections of glass, each no more than 2-3 feet wide with metal posts between sections. When the shot changes and Carla (well, the dummy of Carla) hits, the window is now only two sections, each about 5 feet wide. The easiest way to tell is watch the metal post farthest to the right. When the shot changes to outside, that post, which should now be farthest to the left, has vanished.
Continuity mistake: As Kelso is walking out the door with the blue paint on his face, one hand is on the push bar for the door and the other hand is down. Cut to the shot of him walking out the door and now his right hand is pushing the door open and his left hand is just coming down from pulling the alarm wire above the door loose with no time for him to have changed positions.