Titles in Barron's Painless Series are textbook supplements designed especially for classroom use by middle school and high school students. The approach of each title is an appeal to students who think that the subject is boring, or too difficult, or both. The authors, all experienced educators, take a light approach, showing kids what is most interesting about each subject, and how seemingly difficult problems can be transformed into fun quizzes, brain-ticklers, and challenging puzzles with rational solutions. Geometry becomes painless--and even fun--once students learn the subject's basic components and see how solving any geometric problem is fitting parts together to solve an intriguing puzzle. They learn the meaning of postulates and theorems, discover angles of all kinds, find the relationships that exist between parallel and perpendicular lines, and discover the characteristics of shapes such as triangles, quadrilaterals, and circles. The author introduces real-world geometry experiments to make concepts less abstract, offers study strategies, and demonstrates how mini-proofs are the first step toward understanding formal geometry proofs.