* ActingForTwo: Ellen Travolta played Charles' mother Lillian and her character's own sisters Vanessa and Sally in separate episodes; however, neither character appeared on-screen at the same time.
** Nicole Eggert played Jamie Powell and her cousin Amanda in the episode "Fair Exchange", again both characters never appeared in the episode in the same scenes.
* DawsonCasting: Averted with most of the pre-teen/teenage cast members, the oldest of any of the Powell or Pembroke children in the series (in real life) was Nicole Eggert (born in 1972), who was never more than a year older (at the very least) than her character Jamie.
** Played straight with Scott Baio and Willie Aames, who were in their mid-20s (although, it is assumed that Charles and Buddy are supposed to be college freshmen in the first season); the year-and-a-half gap between seasons one and two left Baio and Aames still playing college students (presumably seniors, though the slowed timeline and the lack of mentions of their characters' advancement in school make this unclear) while they were right around 30 in the fifth and final season (both were born in 1960, the series ended in 1991).
** A double inversion in season five's "There's a Girl in My Ficus": Tiffani(-Amber) Thiessen plays a girlfriend of Charles in that episode. Thiessen however, was 16 when that episode was broadcast in 1990, Scott Baio was almost 15 years older[[note]]It's particularly puzzling when you consider that at the time episode aired, Thiessen was playing high school student Kelly Kapowski in ''SavedByTheBell'', and also the fact that by ''Charles in Charge's'' fifth season, Charles was still supposed to be a college student[[/note]].
* DirectedByCastMember: Scott Baio directed 36 episodes, most of which were during the fourth and fifth seasons; in these instances, he is credited as a director under his (partial) full name, Scott Vincent Baio.
* HeyItsThatGuy:
** Charles is Scott Baio, also known as [=ChaChi=] from ''Series/HappyDays''. Charles may be in charge, but The Fonz is in charge of Charles.
** Buddy is also Series/{{Bibleman}} and [[Series/EightIsEnough Tommy Bradford]].
** Creator/MegRyan played a rival that was critical of Charles' child-rearing techniques (while being interviewed for a position in Charles' nanny agency) in "Charles 'R' Us".
** The guy who Stan and Jill oh, so mistakenly thought was Lila's date in "The Wrong Guy" was [[Series/{{Friends}} Chandler Bing]].
** [[SavedByTheBell Zack Morris]] was a classmate of Sarah's in "Runaround Charles".
** PaulWalker and [[Series/{{Sliders}} Jerry O'Connell]] have played the respective love interests of Jamie and Sarah. [[note]]In the case of Walker, clips of his appearance in the episode "Dead Puck Society" were included in profiles of his career following his death in a 2013 car accident.[[/note]]
** Buddy's sister Bunny in "The Buddy System" was [[Series/TheFactsOfLife Natalie]].
** Melanie (Jamie, Sarah and Adam's youngest cousin in the episode "Fair Exchange") later became [[Series/TheTorkelsons Dorothy Jane Torkelson]].
** [[Series/HappyDays Ralph Malph]] won the lottery instead of Walter (thanks to Charles) in "It's a Blunderfull Life".
** [[Series/LeaveItToBeaver Wally Cleaver]] played Adam's music teacher who crashed their house party (and whom Sarah took in, mistakenly believing he was a homeless man, whom he looked a lot like) in "Summer Together, Fall Apart".
** [[Series/SavedByTheBell Kelly Kapowski]] was Charles' girlfriend, who manipulated Buddy into thinking that Charles didn't want to be his friend, in "There's a Girl in My Ficus".
** Well-known character actor Charles Nelson Reilly played the leader of a religious cult in "Cure for the Common Cult".
** Brian Levant (best known as co-creator and producer of ''Series/MySecretIdentity'') directed two episodes.
** Bonnie Franklin (best known for playing Ann Romano on ''Series/OneDayAtATime'') directed an episode.
** Dwayne Hickman (best known for playing the title character in ''Series/TheManyLovesOfDobieGillis'') also directed an episode.
** Lee Aronsohn (best known for co-creating ''Series/TwoAndAHalfMen'') wrote 13 episodes, a handful of which were with former writing partner Marc Sheffler.
** Chuck Lorre (best known as creator and executive producer of ''Series/GraceUnderFire'' and ''Series/{{Cybill}}'' and as co-creator and executive producer of ''Series/DharmaAndGreg'', ''Series/TwoAndAHalfMen'', ''Series/TheBigBangTheory'', and ''Series/{{Mom}}'') wrote two episodes.
** Jim Vallely (best known as co-creator and co-executive producer of ''Series/RunningWilde'' and ''Series/BrotherlyLove'') also wrote two episodes.
** Al Jean and Mike Reiss (both of whom are best known as creators and executive producers of ''Series/TeenAngel'' and ''WesternAnimation/TheCritic'' and writers for ''Series/TheSimpsons'') wrote an episode.
** Pamela Eells O'Connell (best known as creator and executive producer of ''Series/{{Jessie}}'' and ''[[Series/TheSuiteLifeOfZackAndCody The Suite Life on Deck]]'') also wrote an episode.
* TheOtherDarrin: Jill Pembroke was originally played by Julie Cobb in the first season, however the role was recast with Lisa Donovan for the character's final appearance in the second season premiere "Amityville" (the first episode of the syndication run). It's odd when you consider that Michael Pearlman reprises his role as Jason Pembroke in that same episode.
* RomanceOnTheSet: By most reports, Scott Baio and Nicole Eggert dated towards the end of the show's run (by this point, Eggert was barely a legal adult, although not more than a year or two older than her character Jamie, who was still in high school in the final season).
* WhatCouldHaveBeen: Originally, the role of Charles was written for Creator/MichaelJFox, who declined. Of course, the producers conveniently forgot that Fox was already playing Alex P. Keaton on ''Series/FamilyTies''.
* WrittenByCastMember: Willie Aames is given a "story by" credit in the season four episode "Buddy's Daddy".[[note]]The episode in which Buddy's father visits when he and his mother have marital problems.[[/note]] Scott Baio also wrote an episode.
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