A laid-back high school comedy centering around the daily lives of several characters, including ten-year-old genius Chiyo, space cadet transfer student Osaka, cool but shy Sakaki, overloaded with energy Tomo, responsible Yomi, and sporty Kagura. Also taking part are irresponsible English teacher Yukari, dependable gym teacher Nyamo, honest but extremely perverted Mr. Kimura, and a mysterious yellow cat-thing who may or may not be Chiyo's father.