It really is!
Author Lawrence Leff claims that this book introduces, organizes, and teaches an understanding of geometric principles and explains how to apply those principles in new problem situations. He is absolutely correct. This is a clear and concise exposition of Geometry laid out in logical lessons with helpful exercises and useful tables and charts to help one navigate the material. I turn to this book whenever I need a clear explanation for my son who is frustrated in his high school Geometry course. Included in the book are exercises for each lesson and unit, as well as cumulative reviews, and the answer keys (with explanations) are in the back of the book. The Glossary is thorough and illuminating; the 3-page section entitled 'Some Geometric Formulas Worth Remembering' is priceless. I have searched for a number of years for the best way to teach Geometry -- this is it. Really. (See above headline.)