Education Technology

Storefront Signs

Published on 06/09/2008

Activity Overview

Students learn to find area and explore the quadratic function. They compare the areas and patterns of squares within a square.

Before the Activity

  • See the attached PDF file for detailed instructions for this activity
  • Print pages 71 - 77 from the attached PDF file for your class
  • During the Activity

    Distribute the pages to the class.

    Follow the activity procedures:

  • Draw all possible designs of the square sign in the display window, or construct models using geo boards
  • Record all possible positions of the hooks from the corners
  • For each position, determine the area of the four small triangles surrounding the square, the length of one side of the square, and the area of the square
  • Record the area values in a table
  • Observe that the results are pairs of squares with the same area [except one value]
  • Plot a graph of Area versus Distance
  • Note that the areas get smaller and then get larger
  • Notice that the differences in the areas of successive squares diminish and then grow again
  • Observe that the graph is a parabola
  • Use the graph to determine the area of the largest possible sign and the smallest possible sign
  • After the Activity

    Students complete the Student Activity pages and answer questions.

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