Negima! Magister Negi Magi, Vol. 1 (Negima!: Magister Negi Magi #1)
Ten-year-old prodigy Negi Springfield, has just graduated from magic academy. He dreams of becoming a master wizard. Instead he's sent to Japan to teach English...at an all-girls high school! All the students are delighted with their cute new teacher--except for Asuna, who resents Negi for replacing the teacher she secretly has a crush on.
Although he is forbidden to display his magical powers, sometimes Negi can't resist. And when Asuna discovers Negi's secret, she vows to make his life as difficult as possible--just the thing to prepare Negi for the challenges of life as a master wizard!