Factual error: Kevin and Wayne's bedroom shows a Beatles poster of the White Album. However this album, and presumably the poster as well, didn't come out until November 1968. This season opens with the summer and start of the school year 1968.
Factual error: Paul and Kevin go to the book store to buy "Everything you always wanted to know about sex." In this episode it was still 1968 but the book was not released until 1969.
Factual error: During the scene when the Doors' "Riders on the Storm" is playing. This scene takes place in late 1968, early 1969. "Riders on the Storm" would not be written for at least another year, and the Doors album with that song was released in early 1971.
Odd Man Out - S3-E6
Factual error: Near the end of the episode when Kevin and Paul are riding their bikes toward each other before they stop for a brief hello of sorts, Kevin rides past a couple cars parked on the street that were built in the early 1980's. A red Pontiac LeMans and a black Pontiac Grand Prix-both were parked in front of the 1969 Ford Thunderbird.
Factual error: After the failure to get a new car, the family is sitting around disconsolately watching TV, when a commercial for a new Camaro comes on. However, the Camaro shown is a second generation unit, not introduced until February of 1970, and the Arnolds are still stuck in 1969.
Factual error: During the scene when Kevin visits Winnie through the window after her car accident, a song by Bob Seger can be heard playing. While this scene takes place in 1970ish, the Seger song playing wasn't released until 1978.
Factual error: The gym at the "1972" championship game has a 3-point arc. High schools didn't implement a 3 point line until 1987.