The Study of Angles Book - This material illustrates and describes 20 angle concepts: angle, sides, vertex, size of an angle, whole angle, straight angle, right angle, acute angle, obtuse angle, reflex angle, adjacent angles, vertical angles, complementary angles, supplementary angles, interior angles, exterior angles, alternate interior angles, alternate exterior angles, corresponding angles, and bisector.Includes:book cover20 picture cards20 description cardsThere are two styles of books inclu