Today, I Am a Freshman - S4-E4
Other mistake: In one of the final scenes, Peter ignites his volcano on the patio in front of Marcia and the members of the Boosters Club. As the volcano goes haywire, Marcia and the Boosters are shrieking as the lava/mud covers them head to toe. Somehow Peter, who is much closer to the volcano, is unscathed by the eruption and remains free of any dirt.
How to Succeed in Business? - S4-E19
Plot hole: At one point Peter admits to Greg he was fired. In a later scene, Peter tries to talk the parents out of going to the bike shop (where they think Peter still works), and soon after the parents ride new bikes and see Peter in the park and admit to him that his boss told them what happened. Carol said that Greg filled them in as well. This is incorrect because before leaving the house, they didn't know of the firing, and went straight from the bike shop to the park. Greg never told them.
Suggested correction: Just because we didn't see it on camera doesn't mean it didn't happen, it's known as "implied action."
That's not really the case here... the sequence of events explain it all. It went from going to the bike shop to find out what happened to the park. Even if they went home in-between, there would still not be a reason to have to question Greg, since they know what has happened at this point.
To build on the implied action point that the user stated, we do not know what happened off-screen so it's not impossible to believe that Mike and Carol went home after learning about what happened from the boss to talk to Peter and then have Greg explain where he may be and why. Peter did tell Greg about feeding the pigeons in the park so it tracks.
Fright Night - S4-E6
Plot hole: After the girls get their revenge on the boys in the attic, they explain the mysterious "I must have air" voice from the trunk as it's revealed to be from a tape recorder. Marcia mentions a set up the girls had where they played the tape recording (from their bedroom) when they were ready. This is impossible as the recorder was in the attic trunk and the play button would have had to be manually pushed down by an actual person to activate.
You Can't Win 'Em All - S4-E22
Continuity mistake: The dress in Cindy's arms turns around from one shot to the next; first the back is facing outward, then the front is. (00:14:15)
The Great Earring Caper - S4-E20
Visible crew/equipment: The stage lights are reflected in Peter's magnifying glass. (00:04:00)
Continuity mistake: Jennifer writes her phone number on Greg's right hand with the first number starting at his thumb, but when Greg looks at his hand to read the phone number, the phone number was written with the first number near his fingers and the last number written by his thumb. (00:02:50)
Goodbye, Alice, Hello - S4-E10
Continuity mistake: Greg is wearing dark dress shoes when he comes in to the yard playing football with Peter. When they enter the kitchen, Greg is wearing white sneakers, and when Greg enters the living room, he is wearing the dark dress shoes again. (00:01:15)
