Azumanga Daioh: Extra Lessons

To celebrate the 10th anniversary of Azumanga Daioh, the manga was repackaged into a new three-volume set, which included three chapters of new material called "Hoshuuhen" ("Supplementary Materials" or "Extra Lessons"). Read the full 2009 edition

Each new chapter covers one year of high school, with all new adventures for Sakaki, Yomi, Tomo, Chiyo, Osaka, and Kagura.