How to Teach Angles in Geometry to Third Graders?
In third grade, student experiences with geometric angles are often limited to counting the number of angles in a specific shape. Third graders can also learn to distinguish right angles from other types of angles. These early experiences help students learn about angles and will also help them apply more sophisticated geometry concepts in upper elementary, middle school and high school.
1 Identifying Shapes From Their Angles
To help your students learn about the different shapes that have angles, provide them with a variety of shapes such as parallelograms, trapezoids, octagons, pentagons and triangles. Ask them about the characteristics of the shapes -- including angles – so they will learn how to identify, define and classify the shapes. Focus your students’ attention on the number of angles these shapes have. For example, squares, rectangles and parallelograms have four angles, but shapes that have more than four sides -- such as pentagons and octagons -- will have more than four angles. Instruct your students to classify the shapes by the number of angles they have. Your students could also create a diagram or chart that illustrate their findings about the shapes’ angles.
2 Angles in the ABCs
Use the ABCs as a way to describe angles. Show your students the capital letters "A" and "E," and then ask them to tell you the angles they see. Also ask them to tell you how these angles differ. Show them how to trace over the angles with different colors. For example, you can use one color for angles that are more than 90 degrees – which are known as obtuse angles; a second color for angles that are less than 90 degrees – which are known as acute angles; and a third color for angles that form a shape such as the corner of a rectangle. Corners in squares and rectangles are right angles and are 90 degrees. Give your students paper and instruct them to draw large, capital letter shapes in black, and then to draw in the angles, using a specific color for each the type of angle the letters have.
3 Search the Campus
Take your students on a campus “angle” search to look for objects that have different types of angles. Have them draw the objects or take photos of the different types of angles around campus. If your students are drawing the objects, have them bring index cards and clipboards. If they are taking photographs, print the pictures once everyone is back in class. Then, have your students sort the pictures into those that have similar types of angles. You can then arrange these photos on the wall for a large display.
4 Creating Art With Angles
Using masking tape, a canvas board and paint, your students can create art using angles and then they can count the number of angles in various shapes, comparing and contrasting the various shapes. Give your students a canvas or foam board that’s 8-by-10 inches or larger. Have them place masking tape in straight lines across the width or length of the board in all different directions. Give your students paint and instruct them to paint over the entire board, including the masking tape -- with any colors they choose. Once the board is dry, have your students carefully peel off the masking tape, leaving plain, straight white lines, which creates the sides of multicolored shapes. Have your students analyze the shapes that result, discussing the ways in which the shapes are similar and the ways the shapes differ from each other.