When Teacher Gao takes a leave of absence to tend to his ailing mother, the mayor of the village appoints Wei Minzhi, a mere 13, to take over the class.
Wei protests, feeling unable to teach students her own age and younger, but is told that finding an older replacement in such a rural area would be impossible. Teacher Gao cautions Wei that she must not allow another student to drop out while he's gone, promising her an extra 10 yuan if she succeeds. One student, Zhang Huike, is a bright but naughty boy who often tries Wei's patience as she works to keep order.
But Zhang's family is in serious financial debt, and one day, he fails to appear in class. Wei discovers he has been forced to go to the city to find work so she takes off to the big city to find and bring him back.