Nobita painstakingly makes a new string figure, but ruins it when he bumps into his father while going to show it to Shizuka. Dad then lectures him for not liking boyish games. Nobita recounts the incident to Doraemon at Gian and Suneo's soccer match. Doraemon takes out a spray which makes boys behave like girls and girls behave like boys, and sprays it across town.
When Suneo gets hit by the ball, he starts behaving like a crybaby. Gian scolds Suneo, but when the other boys also comment that he shouldn't criticize him that way, he behaves girlish too and cries as well. Nobita tries to convince the boys to stop playing soccer and pick up cat's cradle instead, but is mocked for talking like a girl.
When the boys are gone, Nobita proceeds to show Shizuka his string figure, but it doesn't interest her. She picks up the ball and gathers the other girls to play soccer, but when Nobita gets injured in the process, they lament that boys weep so easily. When Nobita and Doraemon return home, they find Dad now preparing dinner and Mom reading the newspaper while smoking, to their disgust.
