Continuity mistake: There are two problems with Lisa's Indian burns. When we first see them, she has 4 burns. Then, while she is showing them to the bullies, there are 3, then 4 again. Then, in the very next scene when she is walking with Nelson in the schoolyard, they are gone altogether.
Continuity mistake: When Lisa is watching tapes of Francine's bullying, there is a scene where they are at the pool. Francine is wearing nose clips in this scene. But when Lisa freeze-frames and leans in to closer inspect the shot, Francine's face is shown on the screen without nose clips. They appear again when Lisa exclaims "Of course. The nose clips."
Continuity mistake: When Marge is racing the school bus, as the bus jumps out of the ditch you can see that the bottom of the bus is painted to resemble a skateboard. When the bus lands from this jump, however, the bottom of the bus is an even grey colour.
Audio problem: In the scene where Lisa is presenting her bully repellant at the 'Big Science Thing', when she first walks onstage there are murmurs of disapproval among the scientists, in which you can hear one of them saying, "Let's not listen". But after Lisa sprays the repellant on herself and stops Francine in her tracks, the scientists start murmuring in astonishment. However, if you listen closely, you'll hear the same recording of someone saying, "Let's not listen".
Continuity mistake: Towards the end, when the scientist is trying to give everybody diamonds, a shot cuts to just Marge and Lisa, but out of nowhere Maggie appears. (00:19:30)
Continuity mistake: When they are riding the boat type raft, the stripes change from red on the left and black on the right, to the other way around and then back again.
Continuity mistake: When Bart is eating the grubs, his tongue appears to be green, in all other shots it's back to red.
Continuity mistake: When the Simpsons are on the raft going down the river in Africa they come to a fork and have a choice of going to the left, towards a sunny and nicer area or to the right where it is rainy and gloomy. As Homer tries to steer the raft to the left as he pulls his left arm out of the water and it is covered in leeches but in the next shot of him when we see the arm again the leeches are gone. No way to remove leeches that fast.
Continuity mistake: Milhouse is seen in the school bus during the Lisa segment, even though he was with Bart at the time.
Audio problem: When Homer and Marge are driving to the hospital, Marge says "Let's just say that Bart did it". But her mouth says something else when she says "Bart".
Continuity mistake: The bikes disappear after Bart and Milhouse arrive at the cave.
Audio problem: When Lisa says "Oh no, somebody took my bike", she is mouthing something else.
Continuity mistake: During Lisa's and Bart's segment, time seems to run really quickly. When Lisa leaves West Springfield Elementary it is 11:00 and when she gets to Moe's it is noon, then a few minutes later it is 2:50. When Bart and Milhouse find Fat Tony it is noon, then when Bart gets hit by the truck, it is almost 3:00.
Audio problem: When Bart is going through his keys, he says "Your house", and his mouth doesn't match what he is saying.
Audio problem: When Marge says "We've gotta get to the hospital, Homer" her mouth doesn't move.
I'm Goin' to Praiseland - S12-E19
Continuity mistake: When Flanders' girlfriend pulls up at the end, from one angle she's wearing a pink shirt with what looks like a white vest over top. But from another angle her shirt is all white.
I'm Goin' to Praiseland - S12-E19
Revealing mistake: In one of the scenes (I think it is when they first discover the alleged 'miracle') you can see people in the background walking out of the park. But they are not walking out of the park at all, they are walking into the wall.
I'm Goin' to Praiseland - S12-E19
Continuity mistake: When we first see the "Whack-a-Satan" game at Praiseland, there are three rows of holes the little devil dolls emerge from. After Nelson turns towards Flanders, the game is seen behind him, now with only two rows of holes.
I'm Goin' to Praiseland - S12-E19
Continuity mistake: Helen Lovejoy suddenly has lipstick on when she gives Homer the ice cream. She doesn't have lipstick on in previous shots.
I'm Goin' to Praiseland - S12-E19
Continuity mistake: When the citizens are leaving the park in disappointment, Manjula walks past the screen and has yellow skin, light brown hair and is wearing a blue dress. In the next shot she is back to her normal skin color and is wearing her usual pink dress.
Answer: Willy referred to an encounter he believed he had with actual aliens, while Wiggum thought he was referring to the arcade game.