Unit 4, Lesson 5# Use a circular protractor to understand a 1-degree angle as 1/360 of a turn and explore benchmark angles using the protractor

EngageNY 60 min(s)

In this lesson, students concretely experience angles measurements within a circle increase as one of the angle's legs rotates. Students get a concrete visual of how 4 rotations of an angle one-fourth of the circle is one whole rotation. Students experience this concrete visual with 8 rotations of an angle one-eighth the size of the circle. Then, students extrapolate that 100 rotations are needed to rotate an angle one-hundredth of the circle around the whole circle and that 360 rotations are needed to rotate and an angle one-three hundred sixtieth of the circle around the whole circle. Students apply this understanding that 360 three hundred sixtieths is an entire circle to a protractor and make bench marks angles based on 45 degrees and 30 degree angles.