From Chibi Manga:

Kimari Haneno, 15-years-old. This spring, she enrolled at Shikano Academy's Special Communication department. But on the day of the entrance ceremony, this Communication Department is sentenced to getting abolished. Kimari however, who followed the footsteps of her deceased brother, doesn't want this department to vanish! And so, she starts to act out of character! But what should she do!? Only the president of the all male Normal Department student council holds out a helping hand to her. And he has secret plans to capture the headmaster?!