Mila Kunis was only fourteen when she auditioned for the show. The casting directors required that any interested actors be at least 18 when auditioning. When producers asked her age, she misled them by saying, "Well, I'll be eighteen on my birthday." and neglected to say what year.
Mila Kunis (Jackie) had her first kiss in real life at the age of 15 as an actress on this show with Ashton Kutcher (Michael Kelso). She and Kutcher got married years later and have two children.
The filming of the final episode, "That '70s Finale", was frequently delayed because Laura Prepon (Donna) couldn't stop crying. She had become extremely emotional as the realization that she would no longer be filming the show with the cast and crew she had started to consider as family, hit her really hard.
Debra Jo Rupp (Kitty Forman) wears the same red blouse and floral skirt in her final scene of the final season as she did in her first scene in the first season.
Topher Grace was cast after the show's creators, Bonnie Turner and Terry Turner, saw him in a high-school play. They had attended the play to watch their daughter and were impressed by Grace. Grace had never acted professionally before.