Angles in a Circle

A circle is 360°: 360 ÷ 4 = 90.

Warm-up, learn, try it together, practice, then a quick check. About 15 minutes.

What children learn in Level 88

Angles are measured in degrees, written with a little circle: °. A full circle around a point is 360°.
Cut the circle into 4 equal wedges. Each wedge is a right angle: 360 ÷ 4 = 90. So a right angle is 90°.
Cut it into 6 equal wedges instead: 360 ÷ 6 = 60. Each wedge is 60°, an acute angle.
Two of those wedges together make 120°, an obtuse angle.

Georgia's K-12 Mathematics Standards:

4.GSR.7.2 — 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.