When entering the hotel, the landlady is handcuffed with her hands in front of her. When they are in the hotel room, her hands are now behind her back.
When the teams meet outside Leon's apartment to receive the first clue, the amount of daylight varies substantially between close-up shots of each team.
Shots of the blue team show them in low evening light, while shots of the other teams are in bright daylight.
When the five teams start the game, Adam (David Naughton) is wearing plaid, but when he takes off his yellow shirt in the hotel, he's wearing solid tan.
For the first clue, the telescope readings are 38-22-23/56-10-11. When Marvin enters them, he mutters the numbers 22-23-68-22.
When the Green Team pulls up near the Pabst Brewery, they park in front of the east side of the building at 1910 N. Main Street, on Moulton Avenue. However, from behind they are shown looking in awe at the Pabst Brewery at 1980 N. Main Street with the building at 1910 N. Main to their right, indicating that the scene was photographed off the northwest corner of the building in the middle of N Main Street, inconsistent with their reaction shot placing them in the middle of Moulton Avenue.
The elevator in the Bonaventure Hotel shows buttons for 51 floors. The Bonaventure has only 35 stories.
In the opening credits, Lavitas comes off the football field in a #12 football jersey, but at the 21 minute mark references that he and the rest of the Green Team are an offensive line. No matter what level of football (NCAA or NFL), an O-Lineman wouldn't wear #12.
The corridor outside of room 2704 of the Bonaventure Hotel is portrayed as being long and wide with traditional hotel layout. In reality, the corridors on the 27th floor of the Bonaventure hotel near room 2704 are curved to the distinct shape of the round hotel towers. The actual corridor would not have been suited to the actions portrayed.
When Harold types the first clue into the computer, his hand movements over the keyboard don't even come close to matching the words appearing on the screen.
When Harold's team is finally in the lead en route to the Bonadventure Hotel; Lucille asks Harold to go back for 'Little Harold' to no avail. When Melio and Lucille try and make the projected u-turn, they pull the steering wheel to the right (which would have crashed into a building, not make the u-turn to go back)
In Pinball City, there are several mentions of putting quarters into the machines - the yellow team is even shown getting change and putting quarters in the Star Fire game - despite "TOKENS ONLY" signs on all the walls.
When Laura tears the piece of paper with the LAX clue on it, you can see the paper crease so she will have a straight tear.
When Adam and Flynch get into the elderly couple's car, they're standing in front of a store called Greere's. They exit the car on the opposite side of the street at the exact same location.
When the green team smashes the plastic beer pitchers together in a toast and they break we hear the sound of glass breaking. Also, the pitcher Dirk Blocker is holding was empty in the previous shot. When was it filled up again?
While the yellow team runs to the pool area of the Bonaventure hotel, a light is visible in the reflection of the doors.
When Harold's father is berating Harold in his office, he notes that Adam is "such a successful, enterprising young man." While it is possible that Adam had prior successes that were never mentioned, his current job of freshman college counselor would hardly be considered prestigious.
It's never really explained why or where people know Leon from, despite everyone seeming to be very familiar with him. Equally unexplained is the background to the rivalry/conflict between Adam and Harold or why Harold's father even knows who Adam is.
When Leon and his large group are checking in to the hotel, the desk clerk sees the size of the group and worriedly says, "it's only a double!" However, upon entering the room, it is actually a large suite with plenty of room for everyone.
Marvin and Adam refer to their yellow vehicle as a Jeep, but it's actually a Toyota Land Cruiser.