Lesson Plans (1) | Learning Activities (1) |

View Standards
**Standard(s): **
[MA2015] (4) 23 :

[MA2015] (4) 24 :

[MA2015] (4) 25 :

23 ) Recognize angles as geometric shapes that are formed wherever two rays share a common endpoint, and understand concepts of angle measurement. [4-MD5]

a. An angle is measured with reference to a circle with its center at the common endpoint of the rays by considering the fraction of the circular arc between the points where the two rays intersect the circle. An angle that turns through ^{1}/_{360} of a circle is called a "one-degree angle" and can be used to measure angles. [4-MD5a]

b. An angle that turns through *n* one-degree angles is said to have an angle measure of *n* degrees. [4-MD5b]

[MA2015] (4) 24 :

24 ) Measure angles in whole-number degrees using a protractor. Sketch angles of specified measure. [4-MD6]

[MA2015] (4) 25 :

25 ) Recognize angle measure as additive. When an angle is decomposed into nonoverlapping parts, the angle measure of the whole is the sum of the angle measures of the parts. Solve addition and subtraction problems to find unknown angles on a diagram in real-world or mathematical problems, e.g., by using an equation with a symbol for the unknown angle measure. [4-MD7]

This investigative lesson allows students to identify angle measurements as part of a larger angle. Students will deconstruct 180 degree angles into equal parts.

This is a College- and Career-Ready Standards showcase lesson plan.

View Standards
**Standard(s): **
[MA2015] (4) 25 :

25 ) Recognize angle measure as additive. When an angle is decomposed into nonoverlapping parts, the angle measure of the whole is the sum of the angle measures of the parts. Solve addition and subtraction problems to find unknown angles on a diagram in real-world or mathematical problems, e.g., by using an equation with a symbol for the unknown angle measure. [4-MD7]

This learning activity should be used at the end of a lesson on recognizing angle measure as additive. The students will find missing angle measurements using a real-world problem. This learning activity can be used as an assessment.

*This activity results from the ALEX Resource Gap Project.*