I saw this at some point in the past two years, however, I believe it was created between 1998-2002 BUT I COULD BE WRONG?!? SO. THERE ARE THESE SISTERS. ONE OF THEM IS INTROVERTED, A BURGEONING FEMINIST AND, BASICALLY ME, IF I WAS BORN IN 1989 AND GRADUATING FROM HIGH SCHOOL IN THE LATE 90S. Her sister is basically SHARPAY from High School Musical and, um, sleeps with dudes and has parties. The nerdy sister prefers 2nd wave punk-rock feminist bands (JOAN JETT) who SCREAAAAAAAAAM. She wants to go to a liberal arts college and probably become a lesbian but ONLY because everyone else is. And the secretary keeps writing porn about beef truncheons in a PROFESSIONAL SETTING AT THE SCHOOL?!?!?! SCANDALOUS!
I think you are thinking of Ten Things I Hate About You. http://www.imdb.com/title/tt0147800/combined