 One day , after trying to make the troublemaker Zhang apologize for bothering another student , Wei discovers that Zhang has left to go find work in the nearby city of Zhangjiakou . The village mayor is unwilling to give her money for a bus ticket to the city , so she resolves to earn the money herself , and recruits the remaining students to help . One girl suggests that they can make money by moving bricks in a nearby brickyard , and Wei begins giving the students mathematical exercises centered on finding out how much money they need to earn for the bus tickets , how many bricks they need to move , and how much time it will take . Through these exercises and working to earn money , her rapport with the class improves . After earning the money , she reaches the bus station but learns that the price is higher than she thought , and she cannot afford a ticket . Wei ends up walking most of the way to Zhangjiakou . 
