Geometry is a fundamental part of the mathematics foundation provided by elementary education. Children have an intuitive understanding of geometry that they draw on when dealing with geometric concepts in activities like drawing, playing hopscotch, defending their "half of the room," and playing sports. This book offers no instruction in drawing, measuring, or formal reasoning, but has the goal of giving students in elementary school an intuitive grasp of plane geometry. The book is written for teachers who have had little or no geometry instruction, as well as teachers who know geometry well. It is organized into 12 lessons, consisting of 3 parts: a definition of terms and illustrative examples; an identification exercise; and a "treasure hunt" in the students' immediate surroundings for the geometric figures studied in the lesson. In addition, there are three review exercises and one final comprehension exercise. The answers to all the exercises are provided at the back of the book. The lesson topics are: (1) Perpendicular and Parallel Lines; (2) Right, Acute, and Obtuse Angles; (3) Polygons; (4) Right Triangles; (5) Scalene, Isosceles, and Equilateral Triangles; (6) Quadrilaterals, Rectangles, and Squares; (7) Parallelograms, Rhombuses, and Trapezoids; (8) Pentagons, Hexagons, and Octagons; (9) Circles; (10) Chords, Segments, Sectors, and Semicircles; (11) Inscribed Polygons, Tangent Lines, and Circumscribed Polygons; and (12) Congruent Polygons, Diagonals, and Complex Figures. (MDH)