North Sea Is Death Sea (1976) [Blu-ray]

13-year-old Uwe - "a magnificent screen debut" (Critic.de) by Hark Bohm's adopted son Uwe - lives with his mother and abusive alcoholic father in a Hamburg housing project. When he discovers that the Asian classmate he's been bullying - an equally powerful performance by the director's other adopted son Dschingis - has built a raft from scrap wood, they plan to run away and sail to the North Sea.