National Security Agency
Classifying Triangles
Building on young mathematicians' prior knowledge of three-sided shapes, this lesson series explores the defining characteristics of different types of triangles. Starting with a shared reading of the children's book The Greedy...
Curated OER
Human Geometry Book
Students investigate geometric shapes. In this geometry lesson, students read the book The Greedy Triangle and define the shapes mentioned in the book. Students make the shapes by using their bodies.
Alabama Learning Exchange
Polygons-Changing Area Versus Changing Perimeter
Investigate the area and perimeter of polygons in this geometry lesson. Young geometers use grid paper to draw a quadrilateral and calculate its area and perimeter. They also read The Greedy Triangle to identify the changing shape of...
Curated OER
3-D Attributes
Students explore geometric solids. In this geometry lesson, students listen to the book The Greedy Triangle by Marilyn Burns, then work in groups to sort geometric solids into various categories. Students define geometric solids...
Curated OER
Math: Geometric Fun and Games
Third graders discover geometric shapes by completing a series of games and activities. Using ropes with knots tied every foot, they make shapes such as squares, triangles, and hexagons. In pairs, 3rd graders use pattern blocks to...