Lance's position behind the bar counter changes several times as Stumpy tells everyone about the '80s.
When Majors shows the employees of Bull Mountain their new uniforms, the jacket he holds up has the Team Snownook initials embroidered on it, even though the name Snownook hadn't been chosen yet.
In one of the last scenes of the movie, when Rick and Jenny are talking atop a mountain, a sign can be seen in the background that says "Hangman's Peak". When the shot changes to an aerial view of them descending, the sign is gone.
When Rick goes to talk to Jenny about missing the date she's putting bags in the back of her car. Only the window is popped open in the back but in the next shot she closes the whole door.
In the King of the Mountain race, Jenny flashes Pigpen. In the scene in the bar, before the race Jenny is shown wearing a sweater with a vest over it. It would be impossible for her to merely open her jacket and reveal her bra, given what she was wearing.
The Alaska flag on the pole in Snownook is upside down throughout the movie.
When the guys start pushing the car to pull the prank on Luke, in one of the scenes shot from above you can see that the car does not leave any tire marks in the snow.
When the statue of Papa Muntz is sliding down the mountain at the climax of the film, you can see a cable held taut in front of the statue, supposedly controlling its decent.
When Anthony falls during the king of the mountain race, he swears quite audibly. However, when he turns over, he spits out a lump of snow which would have prevented him speaking so clearly.
Major's Hummer has a Dueck GM sticker on it, a Vancouver (where the movie was filmed) dealership - despite his Colorado license plate.
After the random drug test, Pigpen is heard saying, "I don't need to take a test to tell you I use drugs," but his is mouth never moves.
When the statue of Papa Muntz is sliding down the mountain at the climax of the film, you can see a cable held taut in front of the statue, controlling its descent.