Girl's High(2006)

Joshikousei

Eriko and her friends Yuma and Ayano are excited about entering high school. Their excitement leads to their breaking of the rules when they toured the school before the opening ceremony. They find out their preconceptions about the all female school may not be as true as they had first thought. Despite that, Eriko and her friends are joined by new friends. They aim to get through high school life together.

(Source: Anime News Network)