Happy Lesson (stylized as HAPPY★LESSON) is a comedy manga, written by Mutsumi Sasaki and illustrated by Shinnosuke Mori, 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.

The plot of Happy Lesson 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.

This first adaptation took the form of a five-part OVA, featuring how the main character meets with the teachers, as well as how he is reunited with his childhood friends, Hazuki Yazakura and Minazuki Rokumatsuri, from the orphanage.

Stig Hogset from Them Anime Reviews said that "the show itself actually manages to balance its comedy with the drama, neither one really overlapping or distracting the audience from the main content".

[1] Don Houston from DVD Talk review stated that it "was a fun, cute, and even interesting way to spend several hours as Chitose and his gang of lovely teachers handled the various situations they got into with a sly grin and a knowing wink".