Classifying figures by features is a fundamental geometry skill. Use this lesson plan to teach your students how to categorize triangles by internal angle types.

Shape up your students' understanding of geometrical attributes with this hands-on math lesson. Students will gain a better understanding of how to describe a shape by the number of edges and vertices it has, rather than by its name.

Make a math mystery! In this lesson, help your students understand the relationship between addition and subtraction and how a missing addend word problem is represented with a number sentence.

Teach your students to find the perimeter of polygons using real world examples. They will make polygon pictures using tangrams and practice finding the perimeters of the polygons in their masterpieces.

This lesson on perimeter will let your students walk around the class to see the border, use a measuring tape to measure the walls in their classroom, and enable them to understand how math is related to real life!