Maid Sama!

Seika High School, once an all-boys school notorious for its wild students and for generally being a terrifying place for girls, has recently become a co-ed school. With the female population still a minority and living in fear of the over-the-top antics of the males, Misaki Ayuzawa takes it into her own hands to reform the school and allow the girls to feel safe in the rough environment. (imdb)