Bert is finally turning 13. After years of waiting, he is finally becoming a teenager. For his birthday, he wants Rebecka from the parallel class, wrapped in shiny foil or jumping out of a cake. The worst thing that can happen in life is a health check, especially if you are 13 years old. Bert, Åke, Klimpen, Torleif, and the other boys in the class sit petrified with fear, waiting for the extremely terrifying Sister Ilse. The class is raising money for a class trip. Bert comes up with an idea—th...