- p. 6Wedges of a Circle. Find the measure of one wedge by completing each number sentence.
- p. 7Count the Wedges. Count the wedges inside each angle, then write its measure with the degree symbol.
- p. 8Unit Angles. Count the unit angles that fit, then write the measure with the degree symbol.
- p. 9Read the 360 Protractor. Estimate, then read the protractor, writing the measure with the degree symbol.
- p. 10Measure on the Protractor. Read the protractor, check each reading, then write it with the degree symbol.
- p. 11Use Your Own Protractor. Use your protractor, write each measure with the degree symbol, then circle its name.
- p. 12Angle Stories. Read each story, show your thinking, then write the measure with the degree symbol.
- p. 13Angle Code. Answer each question, writing measures with the degree symbol, then spell the word.
- p. 14Mixed Review. Solve each problem, writing angle measures with the degree symbol.
The standard
Measure angles in reference to a circle with the center at the common endpoint of two rays. Determine an angle’s measure in relation to the 360 degrees in a circle through division or as a missing factor problem.
Element 4.GSR.7.2 of Georgia's K-12 Mathematics Standards (2021, effective SY2023-24), in the Geometric & Spatial Reasoning strand. It sits under standard 4.GSR.7: Investigate the concepts of angles and angle measurement to estimate and measure angles.
What students practice
Divide 360 by the number of equal wedges, complete missing-factor number sentences, and count wedges or unit angles before using protractors. Printed protractors have one scale, zero on the right, and numbers increasing counterclockwise. Students estimate, read, critique a reading, use a classroom protractor, and solve two angle stories.