Maruko doesn't solve anything or learn a lesson that sticks. She just exists as a kid, messy and stubborn and real, complaining about her allowance one day and genuinely worried about fitting in with her group the next. The movie catches something most children's shows miss: the actual texture of being nine, where your biggest problems are small enough to fit in a school day but heavy enough to matter. You watch her navigate the stupid, ordinary weight of childhood friendships, and it hits because nothing is dramatized.

Nine-year-old Maruko is a mischievous girl whose days feel true to real childhood. She plays tricks on her grandfather, spends hours deciding what to do with her allowance, and cannot stand being seated beside boys she thinks are ugly. When the second term begins, the class splits back into small groups, and Maruko lands with two unruly boys who treat her as their underling, leaving her under plenty of pressure at school. As the athletic meet draws near, the whole class starts training, Maruko included, though her laziness sometimes makes her late. Along the way she notices that the two boys compete over everything, and that underneath the rivalry they share a deep, solid friendship.