Factual error: This film takes place in the mid-to-late 40s. The doorknobs throughout Ralphie's house are too modern for the type of doorknobs used in homes built in that era. This is especially obvious in the kitchen scene when the furnace is smoking and you see the cellar door and in the bathroom scene, when Ralphie is decoding the "secret" message from Pierre Andre. No bathroom door of that era would have a doorknob like the one shown in the film.
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.
Factual error: Ovaltine stopped sponsoring Little Orphan Annie in 1940, and there is a date of 1940 stamped on the decoder Ralphie got in the mail. The Wizard of Oz was released in 1939. The movie setting, therefore, would have to be 1940. The chattering teeth seen in Miss Shield's desk weren't invented until 1949. (00:15:55 - 00:33:50)
Factual error: During the tongue on the flagpole scene, the police car that pulls up is a '46 or a '47 Chevrolet sedan. If this movie is supposed to take place pre-WWII, that car wouldn't have existed yet.
Factual error: The narrator explains of the broken lamp that later that evening he (dad) would bury it next to the garage, however with that much snow and cold in December, the ground would be frozen and he would not be able to dig through it without some serious time, effort and equipment.
Factual error: Early in the film, while the kids are looking at the toys in the Higbee's store window, two uniformed soldiers are visible right behind the kids. The female soldier is wearing sergeant stripes on her sleeves, but the braid on her garrison cap is gold - a color reserved for commissioned officers.
Factual error: In the beginning of the movie, when they are in front of Higbees, there is an RTA sign on the building in the background. RTA in Cleveland did not exist until around 1975.
Factual error: In the opening street scene a Salvation Army band is playing Christmas carols. These arrangements were not written or published until the 1950's.