Continuity mistake: When we see the picture of Mary Bailey on the flip chart, the wording "Actual Photo" underneath the picture changes position between shots.
Continuity mistake: During the meeting with Mr Burns and his political advisers, there is an adviser in front of the flip chart and you can see it is a blank sheet of paper. But a little later on, the flip chart now has the front sheet on top.
Continuity mistake: When Mr Burns attempts to bribe the Government Inspector in his office, his nameplate is on the door. When Mr Burns shuts the door to leave the Government Inspector alone with the money, his nameplate is gone.
Continuity mistake: When we see Mr Burns and Mr Smithers in the office at the Springfield Nuclear Power Plant, you can see there is a rectangle on the wall. When the inspection team arrive, the rectangle has gone.
Continuity mistake: When Bart and Lisa are fishing outside Springfield Nuclear Power Plant at the beginning of this episode, you can see there is nothing on the banks behind them. When Dave Shutton approaches them, some rocks have appeared.
Continuity mistake: When Lisa comes down the stairs prior to watching "When Buildings Collapse", the TV screen is near enough in the corner of the living room and can be seen from the stairs. When Lisa enters the living room, the TV has moved further into the room. Subsequent shots of the TV move it so far into the room that it would not have been possible to see it from the stairs at all in the first place.