These two children are playing the encampment game.
The rectangular square drawn on the ground represents the prospective territory either one will occupy.
They start the game by doing Janken -Rock, Scissors, Paper.
Janken is a typical way children decide who goes first in a game.
Children hold out one hand at the same time representing a rock (a clenched fist), a piece of paper (an open palm) or a pair of scissors (extended index and middle fingers).
The rock beats the scissors, the scissors beat the paper and the paper beats the rock.
The one who wins Janken will draw a semi-circle with his finger by fixing his thumb at the circle center, starting from his side of the territory.
Each time the player wins Janken, he can expand his encampment.
The player who occupies the territory with the most spaces is the winner of the game.