Stacie & Gracie (also named Noreen and Doreen on Wikipedia) are characters from the 1982 movie Grease 2. They are students of Rydell, often mistakenly called `sorority girls' on some movie sites, but they're in high school (sororities are college) and they dress like cheerleaders, so they're more accurately labeled `Cheerleader Twins' (or jokingly nicknamed the Doublemint Twins - which the twin actresses actually portrayed in the '80s).
Stacie & Gracie were exceptionally pretty, high-spirited, very slim and energetic, but they were as popular in Rydell as a case of skin rash. If `irritating’ took a human form, it was those twins. Stacie & Gracie and the Pink Ladies had a rivalry, as they believed themselves to be better than some sexy, young, pink satin-wearing trollops. The Pink Ladies were experts at put-downs. "Virgin alert! Virgin alert! All male periscopes down!!"
They greeted Ms. Yvette Mason during Back To School Again, complimenting her glorious, heavily sprayed high-piled up-do. Gracie stated, "I love your hair, Ms. Mason!" When Ms. Mason thanked them and departed, they chorused, "All 300 pounds of it!"
In the first week of school, Stacie & Gracie had heard that Michael Carrington knew how to play the piano, so they accosted him while he was jogging on the track, and pleaded and begged until he acquiesced to their request (demand, actually). "I will not take `no' for an answer!!"
At the night of the June Moon Talent Show, Stacie & Gracie really looked beautiful, and they were tasked with the job of handing out the two LP record certificates (50 for the boy's division, 50 for the girl's). Stacie was present when the soaking-wet Brad and the Prep-Tones watched as the T-Birds won the boy's division with Prowlin'.
At the Luau, Stacie & Gracie danced with Brad and the Prep-Tones. Later, not caring that Stephanie Zinone was heartbroken over Lone Rider's demise, they made fun of her for her sullen mood, and were threatened with a smack-down with Steph's bamboo baton.
After the Cycle Lords were defeated by Lone Rider's reemergence, enraged that the punks had destroyed the festivities, Stacie & Gracie gang-rushed Leo Balmudo and knocked him into the Pool of Enchantment, alongside two of his gang. So, in a way, Stacie & Gracie became Rydell heroes.
They were played by Jean and Liz Segall (but not necessarily in that order)