Lesson Plan
Illustrative Mathematics

Lines of Symmetry for Quadrilaterals

For Teachers 3rd - 5th Standards
Explore how lines of symmetry help define different categories of quadrilaterals. Looking at a square, rectangle, trapezoid, and parallelogram, young mathematicians discover that each shape has its own, unique symmetry. Encourage your...
Lesson Plan
Improving Measurement and Geometry in Elementary Schools

The Sum of the Interior Angles of a Polygon

For Teachers 4th - 5th Standards
Junior geometers discover that polygons can be decomposed into triangles and that the number of triangles can be determined by a rule. Note that the Geometer’s Sketchpad® software is required to carry out all components of this...
Unit Plan
Curated OER

Linking Lines to Landscape

For Teachers 5th - 8th
Students evaluate art to enhance their core knowledge of fiction, American folk heroes, and the water cycle. In this art lesson, students complete a unit of activities to use art to study various topics of literature, history, and...