In order for a child to learn how to solve problems quickly and correctly, practice is needed. The manual has been prepared in accordance with the requirements of the Federal State Educational Standard for Primary General Education and can be used with any of the existing mathematics textbooks for the 1st grade. Regular work with the book will improve students' academic performance and interest in the subject.Studying the manual, students will be able to consolidate the skills of solving various types of tasks for addition and subtraction in one and two actions within 20 | learn to analyze information and understand the learning task.The book will be useful for 1st grade students for developing and consolidating counting skills, solving problems, preparing for tests and tests, as well as primary school teachers as an additional didactic material in mathematics lessons.