Continuity mistake: When Kitty comes downstairs to give the gang cookies, she tells Eric that she picked out an outfit for him to wear on career day. He then turns and mouths the words "Help me." In the next shot you can see Jackie sitting on Kelso's lap when in the previous episode, she broke up with him. In the next shot she is standing behind him. (00:01:00)
Punk Chick - S1-E22
Other mistake: Jackie and Kitty are baking a pie in the kitchen and Kelso walks in. Jackie and Kelso have an awkward encounter as if they are separated, but they got back together at prom.
Visible crew/equipment: When Jackie tells Eric that she can really use a friend right now, in the next shot facing Eric just as he says, "Okay, well, good luck with that," the camera and crew member wearing a blue shirt can be seen at the left side of the screen. (00:01:00)
Factual error: When Mrs. Foreman gives Fez and Hyde Snack-Packs after they are caught trying to steal beer, they are in clear plastic containers. From 1968-1984, Snack Packs were in cardboard containers with a tin bottom and a tin pop top. From 1984-1990 they were in plastic containers, but not clear ones. It was not until 1990 that Hunts introduced the clear plastic containers.
Who Are You - S6-E15
Factual error: In this episode, when Donna and Jackie are arguing about who is going to go outside, Jackie is seen holding a box of Chips Ahoy cookies. The logo seen on the box was used in the late 90s and early 2000s, rather that the logo used in the 1970s. (00:17:30)
Factual error: The city of Winnipeg is spelled incorrectly on a road sign that appears while they are at the border, spelled 'Winnepeg'. (00:09:35 - 00:10:10)
Factual error: Eric makes a reference to "Sophie's Choice." This episode is set in 1978, but the book "Sophie's Choice" wasn't published until 1979, and the film adaptation wasn't released until 1982.
Burning Down the House - S2-E15
Factual error: Eric quotes "I'm not a doctor but I play one on TV." That quote was from a commercial in 1984.
Visible crew/equipment: As Donna plays footsie with Eric in the car while driving up to Jackie's ski lodge, a crew member's arm can be seen in the backseat. (00:05:17)
Good Old Fashioned Lover Boy - S8-E11
Continuity mistake: While St. Christine and Jackie speak about honesty, the brownies in Jackie's hand suddenly switch to Christine's hands in one shot, then return. (00:20:05)
Continuity mistake: When Donna introduces Sarah to the gang, she states that it took her 6 months of sorting records to become 'Hot Donna'. In season 3 episode 14 "Radio Daze" Donna has just started working there and gets the name 'Hot Donna' immediately. (00:01:20)
Character mistake: Kitty wants to reunite Bob and Midge together, saying it will reunite their only daughter. Bob has 3 daughters (just seen the younger one once). (00:12:30)
Revealing mistake: Hyde claims he's reading a Mad Magazine spoof of Smokey and The Bandit. Look closely at the issue, and he's actually reading a spoof of the movie Dog Day Afternoon. That and Mad Magazine didn't make any parody of Smokey and The Bandit.
Revealing mistake: When Fez and Suzy first meet, they do "12345 you owe me a coke" you can see Kelso mouthing the same line as well. (00:08:04)
Other mistake: Jackie comes out of her room while Fez has Caroline over, stating that she has to use the bathroom. However, in a previous episode, during Fez and Kelso's fight for the same room, it is the room that "has its own bathroom." (00:16:00)
Character mistake: When Bob shows up in the driveway with the free calendar from Red's muffler shop, the calendar says "Foreman and Son." Their last name is spelled "Forman" without the E.
Continuity mistake: When Hyde enters the scene, his shirt is somewhat tucked behind his belt. In the following close-up shot his shirt is above the belt but returns to the tucked position in the next shot. (00:00:10)
Other mistake: How did Donna take the SATs with the rest of the group if she was going to a different school? She is even wearing her catholic school uniform.
Factual error: At the start of every episode we see the gang driving. Cars in the background are not from the 70s but the late 90s. For instance, the truck that comes up beside them at the end is a 90s Ford F150.
Continuity mistake: When Jackie leaves the basement and Lorie comes down she's wearing green pants, but as soon as she walks away they're blue jeans. The shirt, jacket are the same, but it's the pants that change.
Answer: It's Ashton Kutcher's dog.