Young pioneer-leader Ivan is trying to gain credibility among the twelve-year hooligans. Cope with them can only experienced teacher - pioneer-leader Alexandra Petrovna. On top of that, a group of guys run from the camp to the forest, where they bake potatoes in the ashes and sing songs. For this they are threatened with an exception from the pioneer camp. Ivan decides to postpone his studies, take bail for children and join the pioneer life. He takes part on an equal footing in the daily life of his detachment and wins authority.