a five-part OVA series in 2001; a thirteen-episode animated TV series in 2002; a sequel TV series, called Happy Lesson Advance, in 2003; and a second OVA series, Happy Lesson: The Final, in 2004. is based on five teachers who end up living with a troubled and indifferent orphan and their unusual plan to become mother figures in an effort to make him a productive student. To achieve their plan, they employ various methods, such as science experiments, spiritual cleansing, physical training, and hijinks.
Resembles a harem anime.