Continuity mistake: On Christmas morning when they open presents, the sleeves on the mother's robe move back and forth between rolled up and rolled down.
Continuity mistake: As Ms. Shields lectures the children on what happened to Flick, the phrase "the quick brown fox jumps over the lazy dog" is written on the blackboard behind her. But when she is done lecturing them, she turns around to reveal "A Theme: What I Want for Christmas" written there instead.
Continuity mistake: When the dogs steal the turkey and wreck the kitchen, there's a scene of the table broken and no pot holder is on the table. In the next scene, there is a pot holder sitting on the broken table.
Continuity mistake: When Randy is getting dressed for school, his mittens keep appearing and disappearing from his hands.
Continuity mistake: In the school classroom scene, the teacher writes "Silas" in cursive on the blackboard and very emphatically dots the "i" in Silas with her chalk. The dot is visible then and even in the long shot from the back of the classroom, however, in the next, more close-up shot, as the students are filing past her desk and handing in their fake buck teeth, there is no dot above the "i". (00:15:20)
Continuity mistake: In the second kitchen scene after Ralphie sits, the camera looks at the cellar door, where you hear the old man cussing up a "cloud of profanity that still hangs over Lake Michigan." The damper controls are sitting top to the left, bottom to the right. After the "accident" with the lamp, dad comes upstairs. The controls are now reversed, top to the right, bottom to the left.
Revealing mistake: One shot of the family opening the Christmas presents is from above; if you look quickly near the top of the screen you can see the ceiling cut away and even shadows moving on this area - obviously a set piece.
Continuity mistake: In the living room scenes, on the mantel in front of the clock, lighted candles appear and disappear during the movie.
Visible crew/equipment: Right when Adult Ralph says "A C+?", Ralph looks from his paper to the blackboard. Near the bottom of his rights glasses lens, you can see a stage light reflected in it, as well as the silhouette of a crew members head. Do not mistake it for the classroom light reflected near the top of the same lens.
Factual error: On Christmas morning when the Parker's are opening gifts, several Christmas songs can be heard playing in the background. Several of these were released long after when the movie is set (around 1940), particularly Bing Crosby's performance of "It's Beginning to Look a Lot Like Christmas," which was released in October of 1951.
Character mistake: Right after the firefighters have removed Flick's tongue from the flagpole, notice the police officer on the left (Flick's right). He is wearing his sidearm on his right but his Sam Browne cross strap is attached to his belt on his left. The whole point of the cross strap is to support the weight of the sidearm, so the officer is wearing it backwards.