Happy LessonHappy Lesson.

Happy Lesson (stylized as HAPPY★LESSON) is a comedy manga series, written by Mutsumi Sasaki and illustrated by Shinnosuke Mori, which was serialized in Dengeki G's Magazine from April 1999 to September 2002, featuring a high school student who is adopted by five of his teachers. It was adapted into a five-part OVA series in 2001; a thirteen-episode animated television series in 2002; a sequel television series, called Happy Lesson Advance, in 2003; and a second OVA series, Happy Lesson: The Final, in 2004. The series has also been adapted into a series of drama CDs and a Dreamcast game.