A larger amount of colored pearl sticks with gray sticks from 1 to 10 in between is laid out in a serpentine shape. Counting to 10, add the colored pearl sticks and subtract the gray ones. The result, expressed by golden sticks of ten, can be positive or. The material consists of a tray with four boxes: one with five colored pearl staircases, one with five gray pearl staircases, another with a black and white pearl staircase and the fourth with 23 gold tens sticks.