These tutorials are designed to revive interest in elementary methods for solving geometric problems. They provide vivid geometric information that was not included in the modern school textbook. For example, Euler's formula, the circle of nine points, Ptolemy's theorem, geometric inequalities, and more. The third volume is the final in a series of books on elementary geometry. His writing was not planned in advance. However, after the publication of the first two volumes, the author developed and gradually intensified a sense of incompleteness, despite the approving reviews of colleagues and readers about their content and style of presentation. The books are addressed to everyone who wants to expand deepen their knowledge of elementary geometry, from middle school students to mathematics teachers and students of pedagogical universities.