The Olympiad tasks presented in the manual with answers in mathematics, the Russian language, the world around are intended for primary school teachers, heads of methodological associations, teachers of additional education; can be useful for students in grades 3-4 for self-preparation for olympiads and in-depth study of their favorite subject. The purpose of the presented Olympiad tasks is to identify gifted children at the earliest stage of education, develop the creative activity of students, interest in school sciences, ingenuity, ingenuity, determine the level of their theoretical and practical training in the main sections of the primary school program.