Continuity mistake: The lifeguard's pants at the pool are first black, then dark green, and then in the next scene black again.
Visible crew/equipment: When David Spade is telling the others about his naughty dream and we see Rob Schneider's hot daughter in the background (leading everyone to believe that it was she that he was talking about), a boom mic can be seen at the top of the screen (when the camera is facing the lake).
Factual error: The championship game was in 1978. Thirty years later, in 2008, the coach dies. Lenny rents the lake house for the three-day Fourth-of-July weekend. In 2008, the fourth of July fell on a Friday, not on a Monday as depicted in the movie.
Factual error: Adam Sandler is cooking bacon on the bug zapper, laying the meat on the outside cage. That couldn't happen, since the outside of a bug zapper is not hot and has a covered protection cage to avoid shock. (The cage is what the bacon was lying on.)