Education Technology

Circle Around

Published on 06/09/2008

Activity Overview

Students compute the circumference and area of circles. They understand that the ratio of the circumference to the diameter is a value (3.14) called pi.

Before the Activity

  • Review the relation between circumference and area of circles
  • See the attached PDF file for detailed instructions for this activity
  • Print pages 104 - 106 from the attached Student PDF file for the class
  • During the Activity

    Distribute the pages to the class.
    Follow the activity procedures:

  • Use formulas to compute the circumference and area of circles with a given radius or diameter value
  • Determine the radius [to the nearest cm] of circles whose circumference or area is given
  • Examine the diameters of the concentric circles of the archer's target, and determine the areas of the bull's eye and the area of the circle formed by the outermost ring
  • Calculate the total area of all the shaded rings
  • Determine what proportion of the area of the target forms the bull's-eye
  • Determine what proportion of the area of the target is shaded and not shaded
  • After the Activity

    Students complete the activity pages and answer questions.

  • Review student results
  • As a class, discuss questions that appeared to be more challenging
  • Re-teach concepts as necessary