Lesson Plan
Illustrative Mathematics

Lines of Symmetry for Triangles

For Teachers 3rd - 5th Standards
What can symmetry tell us about triangles? After looking at four examples, learners will come to realize that lines of symmetry are different for equilateral, isosceles, and scalene triangles. Use this guided practice activity as an...
Activity
Beacon Learning Center

Beacon Learning Center: Triangles Side by Side

For Students 3rd - 8th Standards
This comprehensive web lesson describes how to classify triangles by their angle and side measurements. It provides real-world examples and exercises for students to practice the skill.
Activity
Homeschool Math

Homeschool Math: Equilateral, Isosceles, and Scalene Triangles

For Students 4th - 6th
This geometry lesson defines equilateral, isosceles, and scalene triangles, and has a variety of exercises, including drawing exercises.
Activity
AAA Math

Aaa Math: Types of Triangles Based on Sides

For Students 3rd - 5th Standards
Students can practice classifying triangles based on side lengths through a series of self-check exercises and timed learning games.
Activity
Other

Ic Teachers: Shapes: Triangles

For Students 6th - 9th Standards
Are you looking for a very basic website that will explain the basic properties of a triangle? Use this site to learn about the properties of equilateral triangles, isosceles triangles, right triangles,and scalene triangles. There are...
Activity
Illustrative Mathematics

Illustrative Mathematics: 4.g Lines of Symmetry for Triangles

For Teachers 3rd - 5th Standards
The division of triangles into scalene, isosceles, and equilateral can be thought of in terms of lines of symmetry. Aligns with 4.G.A.3.
Activity
Texas Instruments

Texas Instruments: Try Angle?

For Teachers 6th - 8th Standards
In this activity, students investigate properties of triangles by randomly generating possible side lengths for triangles. They learn to determine if three line segments can form a triangle. They also learn to classify triangles as...
Activity
Rice University

Rice University: Cynthia Lanius: Hidden Polygon Activity

For Students 4th - 7th Standards
On this site students are instructed to locate different types of polygons on triangle grid paper. This page can be printed so that students can actually draw them. It also gives a definitions link for each polygon.