This engaging series of childhood recollections tells of an unconventional school in Tokyo during World War II that combined learning with fun, freedom, and love. The school had old railroad cars for classrooms and was run by an extraordinary man – its founder and headmaster, Sōsaku Kobayashi – who deeply valued children's independence, and who was a firm believer in freedom of expression and activity.

Doraemon and his friends travel to ancient Japan where they meet Kukuru. When Kukuru tells them that his tribe has been enslaved by Gigazombie, Doraemon decides to help him.