Georgia Learning Connections

*TITLE: Polygons by Tennille Rushin

*Annotation

Students will learn the names for different sided polygons and then make conjectures about the relationship between the number of sides and the sum of the angles.

*Primary Learning Outcome:

For students to understand the relationship between the number of sides and the sum of the angles in a polygon.

Students will need to learn names of polygons and discover characteristics of polygons.  Questions asked to students:  What do all polygons have in common?  What type of angles make up each polygon?  Do you see a relationship between the number of sides and the sum of the angles?

*Assessed QCC:

QCC 13: Angle components, Angle types

Standard-Identifies the component parts of an angle, its vertex, and sides or rays; and classifies angles as acute, right, obtuse or straight.

*Total Duration:

One class period: 50 minutes

1. GSP
2. paper
3. pencil

Procedures:

Step One

1. Discuss names of different sided polygons up to a decagon. Have students say specific characteristics for these polygons.  5 minutes
2. Have students in groups measure the angles (using protractors) inside a triangle, quadrilateral, and pentagon.  They will find the sum of the angles for each polygon and then make a conjecture as to the relationship between the number of sides and the sum of the angles.  25 minutes
3. Once each group has made their conjecture they will use GSP to create a triangle, quadrilateral and pentagon.  They will measure the angles and determine if they made a correct conjecture.  They can create different polygons and see if their conjecture holds true.  20 minutes
4. The assessment will be the conjecture they made and the polygons they created using GSP.

*Assessment:

The student will be graded on their conjecture as well as their polygon drawings.

Extension:

Students can find the lines of symmetry in the polygons they created and compare their figures to regular polygons.

Remediation:

Students will practice using a protractor and measuring angles.  They will classify the angle and then find its exact measure.