In the final scene, the bells around Prancer's neck disappear and reappear between shots several times.
During the conversation about the existence of Santa and God, Carol eats Jessica's pickle. When Jessica gets up to leave, it has returned.
During the hand slapping between Dr. Benton and Jessica, the former's gloves disappear then reappear on his hands.
Jessica and Carol stand atop a sledding hill and proclaim "We're the first ones!" As they start down the hill the camera angle changes and you can clearly see multiple sled trails.
While Steve and Jessica are at church with Aunt Sarah, John's at home reading the paper. We see Prancer walk past one window behind him and then one on the other side of the room. It starts to snow but at different times, there's snow falling outside one window but then no snow and sunnier outside the other.
The reindeer playing Prancer is clearly female, even though she is referred to as "he" in the film. Both male and female reindeer have antlers, though a female's are smaller and daintier than a male's.
(at around 30 mins) When Jessica is telling her story about the play to John while he's trimming apple trees, there is a shot of her with an apple in the lower right hand corner of the screen. It is not attached to the tree by the stem; it's clearly tied to the branch.
The scene is set in a snowy, cold down in the late fall/early winter. Yet breath from the cold can never be seen emerging from the characters.
Rope can be seen attached to the barn doors to make them appear as though they are swinging in the wind.
At the Prancer Palloza Event, Eric Sardeson, Boy #2 in the movie, tells how when Jessica with a real sickle in hand, is chasing the three boys out of the shed, as they were running out Boy #2 slipped on ice right outside the door and Jessica fell on top of him. The sickle just missed hitting him in the head by inches. This falling incident was cut from the film or was not filmed, but it was something that could have been tragic. Lucky no one got hurt.
When enticing Prancer across the pond, Jessica can be seen saying "come on" twice, but it can be heard only once.
When Jessica is enticing Prancer out of the barn with a cookie, she can be seen saying "Let's go, come on" but you hear "Come on, it's a Christmas cookie".
When Prancer is crossing the pond about 32 minutes into the movie, a crew member can clearly be seen in the background during the shot.
When singing "Hark the Herald Angels Sing", the congregation sings "with angelic hearts proclaim" but the lyrics are "with angelic host proclaim".
John is trimming apple trees before Christmas. That is done between February and April.
From the "non-splintery" broken edges of the smashed deer-statue, it is clear that the statues are plastic, yet Carol states that they are made of wood.