Answer
The answer is two. Eve Arden appeared in two movies belonging to the "Grease" franchise: "Grease" (1978) and "Grease 2" (1982). Her credits in the original "Grease" include playing the scene-stealing character Principal McGee, while in "Grease 2," she portrayed the uptight Principal Hilda Worwood. Despite appearing in only two of the franchise's many installments, Arden's contribution left a lasting impression.