Ohio Resource Center

 Geometry

 Enlarge The Greedy TriangleAuthor: Marilyn BurnsIllustrator: Gordon SilveriaPublisher: Scholastic Inc.Copyright: 1994ISBN: 0-590-48991-7Number of Pages: 36Ohio Standards Alignment: Grades preK–2This story invites children to imagine what happens to shapes as they get more sides and more angles.  As the shapeshifter keeps adding more sides to a triangle, the text introduces children to the names of the resulting polygons and shows representations of them in the real world.  The author includes a discussion of the mathematical ideas and suggestions for extensions at the end of the book.  Go to: How to Use This BookHighlights and InsightsRelated ORC ResourcesOhio Standards

 How to Use This Book Children take a walk to look for shapes in the real world. Focus on a single shape, such as a triangle, and have them draw what they see. Have students tell you what they have seen in the shape of a triangle after you read the first four pages. After reading the next four pages, ask the students to identify quadrilaterals that they see. Continue to use the book in this way until finished. Children select a polygon and think about what it might be a part of. When they have an idea, they should attach their polygon to a piece of paper and draw a picture around it. Create a picture using the various shapes from the book. Have the children cut out an assortment of these shapes and make a "cool" picture with their shapes.
 Highlights and Insights The book is meant engage children in the topic of polygons. Each new polygon stimulates the child's imagination as to where that polygon could be found in the real world. Accurate information is included about the subject of polygons, and the author explains that polygons can approach being a circle as the number of sides increases, but that a circle is not itself a polygon.