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: 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.