From Wikipedia:
The Facts of Life is an American sitcom that originally aired on NBC from August 24, 1979, to May 7, 1988, making it one of the longest-running sitcoms of the 1980s. A spin-off of the sitcom Diff'rent Strokes, the series focuses on Edna Garrett (Charlotte Rae) as she becomes a housemother (and after the second season, a dietitian as well) at the fictional Eastland School, an all-female boarding school in Peekskill, New York.
A spin-off of Diff'rent Strokes, the series featured the Drummonds' housekeeper, Edna Garrett (Charlotte Rae) as the housemother of a dormitory at Eastland School, a private all-girls school. The girls in her care included spoiled rich girl Blair Warner (Lisa Whelchel); the youngest, gossipy Dorothy "Tootie" Ramsey (Kim Fields); and impressionable Natalie Green (Mindy Cohn).
The pilot for the show originally aired as the last episode of Diff'rent Strokes' first season and was called "The Girls' School (aka Garrett's Girls)." The plotline for the pilot had Kimberly Drummond (Dana Plato) requesting that Mrs. Garrett help her sew costumes for a student play at East Lake School for Girls, the school Kimberly attended in upstate New York, as her dorm's housemother had recently quit. Mrs. Garrett agrees to help, puts on a successful play, and also solves a problem for Nancy. Mrs. Garrett is asked to stay on as the new housemother but states she would rather remain working for the Drummonds at the end of the pilot.
Following the pilot, the name of the school was changed to Eastland and characters were replaced, with Natalie, Cindy (Julie Anne Haddock), and Mr. Bradley becoming part of the main group featured. Although Kimberly Drummond is featured as a student at East Lake, her character did not cross over to the spinoff series with Mrs. Garrett.
In the show's first season, episodes focus on the troubles of seven girls, with the action usually set in a large, wood-paneled common room of a girls' dormitory. Also appearing was the school's headmaster, Mr. Steven Bradley (John Lawlor), and Ms. Emily Mahoney (Jenny O'Hara), an Eastland teacher who was dropped after the first four episodes. Early episodes of the show typically revolve around a central morality-based or "lesson teaching" theme. The show's pilot episode plot included a story line in which Blair Warner insinuates that her schoolmate Cindy Webster is a lesbian because she is a tomboy and frequently shows affection for other girls. Other season-one episodes deal with issues including drug use, sex, eating disorders, parental relationships, and peer pressure.