In numerous episodes throughout the series, on the first floor of the house, there are two staircases leading up to the second floor; one from the kitchen and one in the living room. But on the second floor, there is only one staircase leading down. And it doesn't matter which one they use, they still end up coming upstairs in the same place.
In later episodes, the door to the attic is located before the last set of stairs in the upstairs hallway. But in earlier episodes, there is no door. Instead, there's just a wall with a picture hanging.
Jesse was supposed to be a High School drop out, however in the episode _"Full House" One Last Kiss (1990)_ when Jesse is at his High School reunion, while he is dancing with his old girlfriend there is a flashback, during the flashback he rides his motorcycle into the gym when his girlfriend says "Jesse, you're going to get in trouble." Jesse replies "I graduate tomorrow, what are they going to do, expel me?"
Jesse has also mentioned that he refused to wear his graduation cap because it would mess up his hair.
When zooming into the girl's room at various points in the show, they zoom through the front window. In a couple of episodes, that window (the only window in the room) is sometimes facing the back of the house and at other times, facing the side of the house to see into Kimmy's yard.
In the episode where Joey is playing in a charity hockey game, the whole gang goes to the ice skating rink. When Jesse is first stepping out on to the ice, he already has big wet spots on his knees.
Kimmy says she and her parents went to Pittsburgh for Wrestlemania VI. Wrestlemania VI was actually in Toronto at The Skydome. Wrestlemania has never been held in Pittsburgh.
Even before the garage is renovated into Joey's room, there are two sets of stairs that lead to it. Most of the time, the cast use the stairs on the left, which leads to the kitchen. There isn't anywhere else in the house that the right staircase could lead to, although Stephanie went up it once in Season 2.
Their TV sat on a TV stand with wheels, and was usually kept against the back wall, and rolled out in front of the furniture only when they watched TV. How did they watch TV? Without any visible power cords trailing every time they moved it, the TV was clearly not attached to a power source.
The Tanners' house number is 1882. But whenever the front of the house is seen, the number clearly says 1892.
In Michelle's room (later DJ's) there is a window on the wall opposite where the camera films from. This is not a wall that leads outside, however. When in the hall, the hallway leads down a few stairs to another hallway to the main staircase. This hallway would be directly behind the wall in the bedroom where there is the window.
After the garage is renovated into Joey's room, a bathroom is added. When the basement is renovated into Jesse's recording studio the bathroom is gone as well as the second stair case.
Once Jesse and Becky moved into the attic, Jesse's grand piano is visible in their living room. Given how small the attic is, as well as the attic door, it would have been impossible to haul a piano that size up there. Also once Jesse and Becky move to the attic, a second bedroom (for the twins) is added as well as a bathroom.
In the "Producer" Kimmy chastises Danny after Becky gets the producers job and tells Danny "You've been on the show longer". This isn't true since Danny and Becky started on "Wake Up San Francisco" at the same time although Danny had been with the station longer as he was a sports anchor in season 1.
The Giants ball cap that Danny buries in 1969 has an orange bill. The Giants didn't start wearing Orange Bill caps until the 1977 season.
In "Just one of the Guys" Stephanie says to Joey they watched this game this morning. No NBA games (especially on the west coast) will air live early in the morning.
Stephanie's sweater is on backwards in the opening credits.
In the basketball episode where Kareem Abdul-Jabbar helps Jesse find his "sweet spot", when Jesse tells the family to leave the court and let him try and figure everything out himself. When he's supposedly alone shooting around, he shoots an air ball and a hand appears quickly in the scene, catches and throws the basketball back to him.
Joey gets his own room when Danny renovates the garage for him. This room is located in the back of the house, down the stairs. However, in the establishing shots of the house throughout the entire series, the garage door is in the front of the house. That means that the garage extends underneath the entire length of the house.
Danny is listed as only child for the majority of the series. Miraculously in "Too Much Monkey Business" he has a sister and Joey has always had a crush on her. Previously she's never mentioned and after "Too Much Monkey Business" airs, she's completely forgotten and Danny is back to being an only child.
When the series begins, Danny is close to 30 and his oldest daughter D.J. is 11 meaning that Danny and Pam eloped after high school yet Pam got pregnant and Danny was able to go to college and get a job as a news anchor after college and have another daughter (Stephanie) after he finishes school. Michelle is born a year before the series airs (1986). However throughout the series Danny and Joey mention that they both struggled to get dates for their senior proms and in the earlier seasons, Danny admits to always liking Pam since junior high but was too shy to admit it.
In "Just One of the Guys" Danny has a 17 year old nephew named Steve. It's not mentioned if it's his brother or sister's son. Since Steve is 17 and Danny is 30, that would mean that Steve's parents weren't much older than Danny and that Steve's parents were 18 or 19 when he was born, similar to Danny having D.J. at 19. Also after "Just One of the Guys" airs, Steve is never mentioned again as Danny is portrayed as an only child as always.
Despite that Jesse and Rebecca got married on Valentine's Day in season 4, they didn't celebrate or mention their wedding anniversary in later Valentine's themed episodes like "The Heartbroke Kid" and "Dateless in San Francisco".
Steve is first introduced as Steve Peters. Later on his name changes to Steve Hale.
In the first seasons of the show Jesse's last name is Cochran but in the later seasons Jesse's last name is changed to Katsopolis.
In one season 5 episode, Jesse is humming the "Bonanza" instrumental theme in joy, while having one of his infant sons on his lap. Then later in an episode of Season 6, Jesse states he hates and cannot stand the theme because during his childhood, his dentist hummed it anytime his teeth were being drilled.
In the first season Jesse brags about sky driving. In season 4, when he is getting married he freaks out about never skydiving before and has to do it before getting married.