During the phone call with Izzi's parents, her father is golfing but wearing a glove on the wrong hand (right handed golfers wear a glove on their left hand).
When Matt goes to Sarah's, Bob requests some gingerbread cookies. What Bob is ultimately given look more like sugar cookies, as the cookies' color is too light to be gingerbread.
The old color lights that Izzi and Matt find in the shed and put up, are not among the lights that are lit. Only white lights are shown lit.
Mila tells Izzi, "Your holiday themed book was supposed to be available for the holidays," referring to the reason she won't allow the final draft deadline past Christmas Eve. Even though the book is for next Christmas, that statement makes no sense in a pure rationale perspective of not having some flexibility in the deadline.