Amityville Horror (the Original) - Self Repairing Windows
At the end of the movie, when the floors and walls are bleeding and the family is upstairs, the windows blow out of the room. This is supposed to be the third floor windows that they show lit up through the whole movie. When the family manages to get out of the house, the house is shown with the windows intact.
It's true that one of the third floor windows blows into the room, however the house had those quarter moon windows on both the front and back. So after the window breaks the windows you see after are the ones on the other side of the house.