(at around 5 mins) Mitch and Frank are standing in front of Frank's car and it has a NYS license plate but those plates were discontinued in 1986. NYS no longer has the Statue of Liberty on their plates.
Darcy's father says that, "It's hard to believe that in just seven months you'll be graduating from high school." This means that the current month would have to be November or December, yet all the trees and shrubbery in the movie are in full bloom.
Mitch-a-palooza is held on a Thursday as stated on fliers. When the college kids goad Frank to have a drink he says he can't because he has plans with his wife tomorrow saying, "We have a nice little Saturday planned." What happened to Friday?
During Blue's Funeral the the navy emblem on the wreath is designated for Naval Officers. The picture of Blue showed him as an Enlisted meaning he should of had a navy emblem not for officers. The coffin should also have had an American flag draped over it.
Frank says that he won't do the beer bong because he had a nice Saturday planned out for 'tomorrow', meaning it would be Friday. Then, the high school girl Mitch sleeps with said she has to get to class, which by then it should be Saturday. The flyers also stated that "Mitch-a-palooza" was on a Thursday night. This means the next day would be Friday.
When Mitch is reading Frank's note about the house being boarded up, not only does Frank's voice-over say things that aren't on the note: "If you're holding this letter, you already know..." but his voice-over doesn't say things that are in the letter: "There is absolutely no way to get inside." and "I love you." The complete voice-over says: "Dear Mitch, If you're holding this letter, you already know. The house has been boarded up. The windows, the doors, everything. We're at the Comfort Inn. Room 112. I love you. Frank." The actual writing on the note says: "Dear Mitch. The house has been boarded up. The windows, the doors, everything. There is absolutely no way to get inside. We're at the Comfort Inn. Room 112. Frank."
When Frank, Beanie and Mitch kidnap Spanish for initiation, he is riding the scooter with a backpack on. In the next shot he is running without the backpack. Then, as he gets tackled into the water, the backpack reappears.
When Megan Huang is playing the tape of Dean Pritchard to Mitch and Frank, the fraternity evaluation committee suddenly appears standing behind them towards the end when Dean Pritchard steals the tape.
At the birthday party right before Frank falls into the pool, he runs into the table. In one shot the birthday cake is on the table as Frank knocks the table down. In the next shot the cake is sitting on a present right as Frank falls into the pool.
At the birthday party, after Frank gets shot with the dart gun, he falls onto a table and knocks over a chair. He falls on top of the chair. In the next shot his arm is through the chair as he is lying on the ground.
When Beanie is in the kitchen describing that they are starting a fraternity, the large black pot on the front left burner keeps moving on and off the burner to the middle of the stove during the scene.
During the scene for school spirit, Frank fails to leap through a ring of fire and his mascot costume catches fire. In the locker room in the next scene his entire body is red from burns. In the next scene, his burns have completely disappeared.
During the exchange between Megan and Dean Pritchard about not holding up his end of the bribe, Megan exclaims, "No one at Columbia has even heard of you!" In a later scene, she plays it back to Mitch and Frank and this line is omitted.
While Spanish and the other guy are trying to get Frank to hit the beer bong, It's Thursday night after 9pm, according to the poster for the party. Frank says tomorrow he has a pretty bust Saturday planned, Home Depot, Bed, Bath and Beyond. Tomorrow would be Friday not Saturday.
In order for their total score to drop from an 85 average to a 58 average with Blue's 0 scores, there could only have been 2 members (3 if you include Blue). In fact, with 15 members, their score could only drop to a 79.6%
In the scene where the gymnastics are taking place, when Vince Vaughn is doing the rings, you can see in the background it says "Harrison University - STATE CHAMPS". Because this is a college university, state champions would not be a possible achievement.