Page 11 - Kindergarten.indd

4.MD.5 – Recognize angles as geometric shapes that are

formed wherever two rays share a common endpoint, and
understand concepts of angle measurement.

OBJECTIVE: Learn how to draw and name angles based on the given measurements.

MATERIALS: (Per Teacher)
12 ping-pong balls
1 empty shoe box

1 marker

MATERIALS: (Per Student)
1 Math Geoboard
1 box of colored rubber bands
1 protractor

LESSON DISCUSSION:
 Define the terms “angles” and “rays”. Give examples of “rays” and “angles”.

 Explain that an angle is measured in reference to a circle with the common endpoint of
the rays as the center of the circle. It is possible to identify an angle 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.

 Explain to the students that an angle that measures less than 90 is called an acute
angle, an angle that measures more than 90, but less than 180 is called an obtuse
angle, an angle that measures 90 is called a right angle, and an angle that measures

180 is called a straight angle.

Procedure:

Step 1: Start the activity by marking the 12 ping-pong balls individually with different
angle measurements. Mark the ping-pong balls with the following angle measurements:
30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, and 360. Each ping-ping

ball will have one angle measurement written on it.

Step 2: Place all the ping-pong balls inside the empty shoe box.

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