The simulator can be used to organize oral counting in the classroom when working both according to the textbook of N. Ya. Vilenkin, V. I. Zhokhov, A. S. Chesnokov and S. I. Schwartzburd, and according to any other 6th grade mathematics textbook. The manual is intended to develop and improve the strong computational skills of students, develop their attention and RAM - the necessary components of successful mastering of a school mathematics course.