Deliberate mistake: Jesse is looking for his keys and thinks Michelle took them. Near the end, Joey comes home and finds the keys in the door, hands them to Jesse, who puts them in his pocket. A few seconds later Danny comes home, takes Michelle into the kitchen. Joey and Jesse exchange a couple lines and go into the kitchen, where Michelle is sitting in a booster chair at the table. The 3 guys chat for a few minutes, then Jesse is going to leave, but can't find his keys again. It turns out Michelle has them. But how did Michelle get them? She was in the booster seat the entire time Jesse was in the kitchen and Jesse never went to that end of the room, so there's no way she could have gotten them.
Deliberate mistake: In the episode January 2011 where Stephanie puts a slide in the living room, when Stephanie goes down it, you can see she is using a stunt double because her hair is thicker and they cover her face with her arm.
Deliberate mistake: To fix the error of the Enterprise firing phasers from the torpedo bay, the Blu-ray version uses footage from "The Best of Both Worlds" to show phasers firing from the dorsal emitter. In doing so, they created a new goof; the planet El Adrel is not visible in the background during these shots.
Suggested correction: I rewatched the original version on the old DVDs. El Adrel wasn't visible in the original either, so this is not a new error.
Deliberate mistake: When the family is trying to get money from Al at the start of the episode, he throws it on the ground making the rest of the family to dive on it and you can see Bud get it, then throw the bunch of money in the middle of Kelly, Peg and Bud so they can all get to it instead of taking it all. (00:02:10)
Deliberate mistake: When the turtles and April escape the building filling up with water, the shot where the hall is filling up with water is used twice.