How to Use a Protractor to Measure Angles

Once your students can name and classify acute, obtuse, right, straight, reflex and revolution angles, it is time for them to learn how to accurately measure these angles using a protractor.

A protractor is a mathematical instrument used for measuring the size of angles in degrees. Protractors come in two sizes: 180 degrees (a hemisphere shape) or 360 degrees (a circle shape).

This poster has been designed to familiarize your students with using a 180-degree protractor to measure acute, right, obtuse and straight angles. The process is explained using labeled diagrams and a series of clear steps that are easy for your students to follow.

Multiple Applications for This Measuring Angles Anchor Chart

This versatile anchor chart can be used in various ways to enhance your students’ learning of measuring angles using a protractor. Here are some suggestions.

1. Print the poster on tabloid paper and display it in your classroom as a reminder of how to correctly use a 180-degree protractor.
2. Print the poster 2-to-a-page and provide the students with a smaller copy to paste into their workbooks for future reference.
3. Project the poster onto your whiteboard, then black out some of the words. See if your students can correctly identify the missing words in the process.

Download, Print, Teach!

This resource downloads as an easy-print PDF. Use the Download button above to access.

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