## Objective

In this geometry lesson plan, elementary school students will learn about common geometric terms and shapes, such as angle, line, triangle, and square. They will practice using these geometry terms and using the shapes that they have learned about.

## Preparation

Cut out plenty of small triangles, squares, rectangles, circles out of colored poster board or construction paper.

## Instruction

Hold up two long, thin strips of cardboard connected together by a paper fastener at their ends. Show students how this device can make an angle. Show them how when the two strips are folded together, it makes a line, but as it opens slightly it becomes an angle. Ask students to keep on saying "Angle! Angle!" as long as it stays an angle, and then to say "Line!" when it becomes a line. Then open the angle very slowly until it reaches 180 degrees, at which point students will call out "Line!" Continue moving the angle beyond 180 degrees while students call out "Angle! Angle!" until it reaches 360 degrees, at which point students will again call out "Line!"

Tell students that angles are all over the place. Give examples of several angles in your classroom, such as the angle between a chair's leg and the chair's bottom, the angle between the wall and the ceiling, or the angles between your fingers when they are spread out. Challenge students to think of other angles around the classroom. Talk about how many angles are in a triangle, a rectangle, a circle, and a square.

## Group Discovery Learning

Cut out strips of poster board that are about an inch wide and two, three, four, or five inches long. In small groups, show students how to connect strings of three or four strips together using brads so that they can be easily manipulated into the shape of a triangle, a square, a rectangle, or a different quadrilateral. Encourage them to use long strips for some and short strips for others (or to combine long and short strips into one shape). Ask them to try to figure out how long each strip needs to be in order to make a square, a rectangle, and a triangle. Students should be able to figure out that any three strips can make a triangle, but that all of the strips need to be the same length to make a square, and that each pair of opposite strips needs to be the same length in order to make a rectangle.

## Review Activity

Have students work in pairs to create a work of art using the paper cutouts you prepared. Students should take turns adding one shape to a large piece of butcher paper in order to make a picture. The only rule is that as a student places down a shape, he or she must specify the name of the shape and how many angles it has. For example, a child might say "I am putting down this triangle, which has three angles, to make the clown's hat." Encourage the children to share their creations with the rest of the class. You can use other fun geometry activities to review this concept as well.

## Assessment

To assess whether students have understood this geometry lesson plan, elementary teachers should listen to students during the review activity to determine whether they understand how the concept of angles relates to geometric figures.

## This post is part of the series: Activities and Lesson Plans for Geometry: Teaching Angles

- Math Geometry Lesson on Angle Types
- Geometry Lesson Plan: Supplementary and Complementary Angles
- Geometry Activities: Fun With Angle Bisectors
- Angles and Shapes: A Geometry Lesson Plan Elementary Students Will Love!