Chibi Maruko chan is the nickname of a sweetly obnoxious 9-year-old girl. She tricks her grandfather, ponders for hours over how to spend her allowance, and hates sitting next to ugly boys. She talks, feels and lives just as real kids do.

As the second term commences, Maruko and her classmates return to their small groups. Maruko’s group includes two naughty boys and Maruko is forced to be one of their subordinates. She seems to face a lot of pressure at school.

As the school’s athletic meet approaches, all the classmates are busy exercising. Maruko is no exception, although her laziness means that she is late sometimes. Maruko realizes that the two boys rival each other in everything they do, and that their friendship is deep and strong.