Amy Poehler
Before her role in Parks and Recreation as well as being a cast member of SNL, Amy Poehler was rocking a feminine dress that contrasts with her recent pant-suits. She went to prom with a strapless ball-gown and a necklace with pearls.
Blake Lively
She is now constantly making us laugh through tongue-in-cheek Twitter exchanges with her husband Ryan Reynolds and has an impressively long resume of movies. Back then, she looked super 2000s chic with her tiara, sidebangs, and blinged out barbie-pink dress.