Yamada Nari manga
Nikotama Souhei is transferring to a new school and vows to enjoy a new life, living a lifestyle true to himself...or herself, as the case may be. Adopting the name "Sara", Souhei heads to school in a girls' uniform, ready to grab life by the knads and twist. Sara's no pushover: bright, hyper and frequently violent. She's like nothing anyone at the school has ever encountered. Especially her sweet, upstanding classmate Naruse Kaito who finds himself knee-deep in Sara's "Brave New World". A nice bit of shoujo fluffiness unique for featuring an honest-to-goodness, non-apologetic transgendered hero(ine).