In 'Hell Week' Chanel Number 3 mentions her sister and how her uncle would warn them not to ice skate on poop lagoons, in 'Haunted House' (when Chanel Number 1 comes up with her Haunted Pumpkin Patch fund-raiser idea) Chanel Number 3 again mentions a sister that is 6 years old. Yet in 'Thanksgiving' when Chanel Number 3 is at her family home there is no sisters nor any place settings for anyone other than her mother, father, brother & their 'help'.
When Dean Munsch opens the oven to check on the turkey to see if it is done yet, you can see that there is one of those plastic red and white pop up thermometers stuck in the breast. There wouldn't be one of those in that turkey because those come in store bought turkeys and the turkey in the oven was supposedly the one that was alive earlier that day and freshly killed, plucked and prepared by Dean Munsch and Chanel #3, who was the first to return from her family's Thanksgiving celebration.
When Chad's mother, Bunny, turns over the hourglass to begin Pictionary, the sand has already run out. If she would like to use it for the duration of the game, she needs to turn it upside down again.