Continuity mistake: Near the beginning of this episode Andrea is awakened at 3 A.M. by an alarm clock to take a pill to stop her preterm labor. Several times in the episode it is mentioned she must take the pill every 4 hours. Later the alarm goes off at 8 PM the same day and she says "time for the pill again that is not doing me any good". If the alarm went off at 3, 8pm doesn't fit the 4 hour timeframe.
Continuity mistake: This is the first episode in which Kelly celebrates a birthday, and it is in March. A few seasons later, Kelly has another birthday, but this celebrated in one of the first episodes of the season and takes place when everyone has just returned from their summer excursions. This would put her birthday in September.
Continuity mistake: At the end of the episode, Steve and John Sears are behind the table and one of them is about to be voted out of the fraternity. Pay attention to the scene where fraternity president Mike Ryan is giving instructions to the other fraternity brothers on how to vote and behave during this process. At the exact scene where Mike Ryan says, 'Your absolute silence is required', in the background we see Steve and John Sears staring down each other in anger. A split second later just as Mike Ryan finishes that sentence, the camera shot now just shows Steve sitting straight forward, looking down at his lap slightly in a kind of sad, defeated state.
Continuity mistake: During the scene where David, Donna, and Andrea are in the casino and Andrea puts one dollar in a slot machine and hits the $500 jackpot, she screams and David tells Donna to get some buckets so that they may put all the coins in them. At that exact moment, they are interrupted by a security guard who asks them for their id's and when he figures out they aren't 21, he asks them to hand over the buckets of coins. At this moment, David and Donna hand over at least one bucket of coins. However, between the time David told Donna to get the buckets and when the security guard questioned them, the gang did not (and had no time to) get to fill up any of the buckets full of coins.
Other mistake: In the scene at the Peach Pit where Rush tells Steve that he is his biological father, he shows Steve a copy of the birth certificate. Under adoptive parents, it lists Sanders, Rush and Sanders, Iris. Only Iris isn't Steve's adoptive mother, Samantha is. Iris is Dylan's mother who lives in Hawaii.
Visible crew/equipment: When the scene changes to Brandon, Brenda and Dylan going to the movies, look closely. You will notice Brenda waiting for Dylan in front of the movie theater. Then later, they show the exact same scene when she is waiting for Dylan to show up on their movie date. It's very quick, but the editors apparently didn't catch it.
Revealing mistake: Pay close attention to some of the scenes on the airplane during the flight that the Walshes are taking to Hawaii. Several times you will see a large, winding (and ascending) staircase in the background of the plane. If you also look close, you will see an 'exit' sign' slightly behind and to the left of the staircase. While some luxury airbuses do have staircases, given the fact you can see an exit sign it is easy to tell these scenes were shot in some kind of setting other than an airplane.
Other mistake: Throughout the entire 4th series and even various times into the 5th series, pay attention to the shots that show the outside of Steve's Kappa Epsilon Gamma frat house. Every single time, you will notice the same exact two people outside of the frat house - one is a guy wearing a green and white striped shirt sitting in the lawn reading a book, and the other guy is wearing a brown or orange shirt lying on the couch outside. While not impossible, these same exact two characters wearing the same exact clothes doing the same exact things outside of the frat house every single time for upwards of a year or more in 'show time' is unlikely.