Leadership Program Exploring Discrete Mathematics in the Classroom

DIMACS || Leadership Program || LP Web Pages || Lesson Ideas

 Created by: Judy Ann Brown LP '92
 Materials: Star of David Picture or Student Worksheet
 Object of the lesson:

Find the total number of triangles in the Star of David pictured at the top of the page.

 Content/Procedure:

1. Show the students the Star of David.
2. Talk about the different sizes of triangles that they see.
3. Help students develop an appropriate vocabulary to discuss the triangles. For example, a size 1 triangle could mean the smallest triangle, while size 2 would refer to the triangles that are made up of 4 small triangles.
4. Have students count the triangles of each size and add them to find the total number of triangles.
5. You might also give the students a copy of the student worksheet and have them color a different triangle on each star.  Mathematical Content:
   The material in this lesson addresses the following 1989 NCTM Standards:
   • Standard 1: Mathematics as Problem Solving: [K-4] and [5-8] and [9-12]
   • Standard 3: Mathematics as Reasoning: [K-4] and [5-8] and [9-12]
   • Standard 4: Mathematical Connections: [K-4] and [5-8] and [9-12]
   • Standard 9: Geometry and Spatial Sense [K-4]
   • Standard 12: Geometry [5-8]
   • Standard 12: Discrete Mathematics [9-12]
   • Standard 13: Patterns and Relationships: [K-4]
    Extensions:
   • Count all the quadrilaterals in the star.
   • Count all the hexagons in the star.
    Other Resources:
   • Hughes, Silver, Math on Display, Creative Publications, 1981.

For more information, please send mail to Judy Ann Brown
Web page created by Judy Ann Brown on Friday, December 12, 1997.