The manual contains detailed summaries of lessons in mathematics, the content of which corresponds to the State Standard of Primary Education and the Standard Educational Program, developed under the leadership of O. Ya. Savchenko. We offer cards for the survey, interesting tasks for oral calculation, samples of conversations while learning new material, tasks of game and creative nature, various methods of working on tasks, exercises of a logical nature, etc. Practical tasks are considered on the basis of schemes, tables, illustrations. The material of the manual corresponds to the textbook "Mathematics. 3rd grade. Part 1 "(author Budna NO, Bedenko MV - Ternopil:" Textbook - Bogdan ", 2020) and provides for the use of textbooks" Mathematics. Workbook. №1, №2. 3rd grade - Ternopil: "Textbook - Bogdan", 2020 (author Budna NO, Bedenko MV).