Third cast member of Charlie's Angels (1976-1982) to be on The Partridge Family, the first one being Farrah Fawcett billed as the "pretty girl" in episode 1.2 and Jaclyn Smith in episode 1.5.
In the scene where Keith is having a burrito and root beer and is talking to Cheryl Ladd, in the background looks like the telephone booth Maxwell Smart gets into during Get Smart's (1965) opening credits.