Pilot: The Spirit of Christmas (Jesus vs. Santa) - S1-E1
Revealing mistake: Each time Jesus turns his head to speak to the children when he is beating Santa Claus, he has two left arms.
Revealing mistake: Whilst Bobby is reversing the truck before hitting the flagpole in Bill's yard we see the driveway in front of the truck. The very next shot shows Peggy from behind the truck instructing him how far to go to the flag pole and you can see they have used the same background as the shot before from the other angle. You can tell this as both shots are the same background as both angles despite from different viewpoints are exactly the same items and objects in both shots. Added to this there is a driveway in each shot, and Bill doesn't have 2 driveways in his backyard.
Revealing mistake: Right after TJ and friends are looking at the "thermometers" of cans, the Ashleys have at least 4 crates of cans that they bring in on forklifts. However, the end result is 4,362 cans for the Ashleys. This may seem kind of picky, but I think there was more cans than 4,362.
Suggested correction: This is literally just an assumption, and nothing else. 4,362 is a pretty huge number, and with the amount of cans that we see the Ashleys collect in the episode, combined with the amount of cans that they and the rest of Miss Furley's class collected off-screen, it is perfectly believable that Miss Furley's class would end up collecting that amount of cans.
Revealing mistake: In every episode, the windows in both the kitchen and living room areas never reveal any scenery outside them during the day or any reflections from the inside at night.
Demon Suite Murder Case: File 2 - S1-E17
Revealing mistake: When Kindaichi looks the name up in the French dictionary, the pages are entirely made up of the same paragraph repeated over and over. (00:08:50)