A film about the Children's Railway as a system of additional education for children, in the format of which a unique system of vocational guidance of schoolchildren in the profession of railway transport is built with the help of games, studies and "work". Moscow region, the village of Kratovo, summer, 1973. Moscow Children's Railway. Park area. The boy plays the pipe, imitating the birds. Wooden building of the Pionerskaya railway station. School-age children in the uniform of railway workers on a railway platform, checking the running gear of the train, inspecting the tracks, giving a signal. View of the departing train "Yunost" from the depot. Outdoor rehearsal of a children's brass band led by a pioneer counselor. Children ride on merry-go-rounds, swim in a pond. A brass band is passing by. The guys get on the Yunost train. The train driver, a teenager Konstantin Gusev, is in the cab. The train starts moving.