Measure the Angle

Designed by: Tammy Hester        School: Gibbes Middle

Core Curriculum:  Students will be able to measure angles using a protractor and identify types of angles.  (7GE3-1)

 South Carolina Curriculum Standards: IV. Geometry and Spatial Sense B. Use technology whenever appropriate to explore concepts and applications of geometry.

Overview: Students should be able to use a protractor to measure angles and use the internet to explore and learn about different types of angles.

Focus Question: Ask students to point out angles they may see in the classroom.

Time Frame: Two 50-minute class periods.

Resources:

Overhead Protractors

Computer

Website: www.mathleague.com/help/geometry/angles.htm

Assessment: Student will pair with a partner and each student will draw 8 angles - 4 obtuse and 4 acute. Students will then trade with their partner and measure the others angles. Students will also list two new things they learned about angles from visiting the website. Each item will be worth 10 points.

Day One

Activity One

1. The teacher should draw an angle on the overhead. The teacher calls on a volunteer to measure the angle. Ask a volunteer to explain that the protractor should be placed so that the center is on the vertex of the angle and the 0 degree line lies on one side of the angle.

2. Discuss the two scales on the protractor. Stress that students are to use the one that begins with zero where the side aligns with the protractor.

3. Follow the scale from 0 to the point where the other side of the angle meets the scale. This is the measure of the angle.

4. Draw at least 5 more angles on the overhead and allow volunteers to come and measure for the class.

Activity Two

Have students write in their journal how they know which scale to use on the protractor. Have some volunteers share what they wrote. Discuss as a class.

Activity Three

Introduce the vocabulary: degrees

• Right angle
• Obtuse angle
• Acute angle
• Straight angle

Have students put these terms with the definition in the vocabulary section of their notebooks. Guide students to the corner of a piece of paper. Ask students to name the type of angle. Explain how this can be used to determine if an angle is more or less than 90 degrees.

Activity Four

Have students go to website http://www.mathleague.com/help/geometry/angles.htm Then, have them click on What is an angle? Next, have them click on Degrees: measuring angles. Students should explore the site because it is a reinforcement of how to measure angles. Students should also discover other types of angles. Student should record at least 5 other things they learn about angles from this site into the journal section of their notebook.

Day Two

Activity Five

Review the types of angles and how to use the protractor. Students should take turns sharing with the class new things they learned about angles from the website.

Activity Six

Using their protractors students should draw and then measure at least five angles. The teacher should constantly monitor and be available to help those in need of further instruction. Students can also work with a partner to assure understanding.

Assessment

Each student will draw 8 angles. The teacher should specify that half be acute and half be obtuse. Students will then trade papers with a partner and measure the angles their partner has drawn. Students should also list two things they learned from the website along with an explanation and example. Allow students to use their notes. (See Rubric.)