The fifth episode. The plot of the fifth episode is: Mr. Zhou called at home, admitted his mistake to the teacher, and promised to go back to school. Lv Shan happily told his mother that the happiest thing today was to apologize to Gu Sui. "We are all good friends" focuses on the children of migrant workers, and tells the touching story that migrant workers go to work in cities, and their children come to cities to receive education, collide, understand and communicate with children in cities, and finally become good friends.