SME
Grade 4 Math
Angles and angle measurement
The main lesson, then each kind of problem it solves.
Angles and angle measurement
Main lesson
Measure angles with a protractor
Use this for “What is the measure of the angle?” on a protractor, either scale.
Measure angles: neither ray on zero
Use this for “One ray points to 45 and the other to 135. What is the angle?”
Understand angles as parts of a turn
Use this for “a quarter turn is how many degrees?” or “how many 20° angles make a full turn?”