1 plot. - The pioneers of Kazan greet the pioneer Olya Balykina at the city meeting, who helped to expose her father on her collective farm, who plundered collective farm property with a gang of thieves. 2 plot. - The Leningrad children's technical station: the guys design airplanes in the aircraft modeling circle, test a constructed trolleybus and a crane. 3 plot. - North Caucasus. Construction of a field mill on the collective farm. Ilyich: the pioneers are helping to make a mock-up of a field camp. 4 plot. - Moscow. Arrival at the 3rd health school of the 2nd stage of the delegation of Austrian Schutzbund people with their children: meeting, gala dinner in the park, games. 5 plot. - Production of children's pedal cars at the Gorky Automobile Plant. Children in cars drive along the city street.