The book presents new interesting tasks that will help children not only to love calculations, but also to receive only five in mathematics. Puzzles with non-recurring numbers are systematized, which will allow them to be effectively used both for the Olympics and holidays, and for training the mathematical apparatus of schoolchildren. As a result, elementary students will remember the multiplication table faster, and high school students will be able to develop their creative and combinatorial abilities. An important section of the book is "Pages of History", which for the first time indicates alternative solutions to the most famous problems. It is especially necessary to pay attention to the largest list of books to date, where there are pages devoted to entertaining mathematics. For students of grades 1-7, teachers, heads of mathematical circles, parents, methodologists and all those interested in puzzles