Laura Prepon's character (Donna) originally had two sisters. One sister, Tina, appeared in the episode "Eric's Burger Job", and the other, Valerie, was mentioned in "Eric's Birthday". Much like Chuck Cunningham from "Happy Days (1974)", they were quickly phased out and never seen or mentioned again.
The skit with Kelso (Ashton Kutcher) and Forman (Topher Grace) titled "Doofus and Diligent" is based on the comic strip "Goofus and Gallant", which has been printed in the magazine "Highlights for Kids" since 1948.
Last of three appearances of Jackie's father.
Laura Prepon (Donna Pinciotti) & Amanda Fuller (Tina Pinciotti) also worked together on "Orange Is the New Black (2013)" as Alex Vause & Badison Murphy, respectively.
First of two episodes in a row to feature a "one-off" appearance. In this episode, Donna's sister, Tina, makes her only appearance. In the episode immediately following, Eve (Jan Brady) Plumb makes her only appearance as Mrs. Burkhart.