Students learn to recognize common geometric shapes and all three types of angles (obtuse, right and acute) by manipulating this set's eight shapes, 16 double - sided Activity Cards and Angle Ruler. Includes a square, rectangle, isosceles triangle, right triangle, scalene triangle, equilateral triangle, octagon and parallelogram. Each shape features degrees on one side for self checking. On the reverse side, individual letters appear in angle vertices for angle identification. Made of durable plastic, each shape measures approximately 4".