Problem:  The teacher of Joe’s art class assigned the task of creating business signs that would contain the name of a business.  These were the guidelines students were given to follow:
· The signs must be composed of equal-sized squares.
· One-third of the squares must contain letters.
· One-third of the squares must be white.
· One-third of the squares must be shaded.
· No pictures can be included in the signs.

Three of the signs that were turned in are shown below.  One of these signs does not follow the guidelines.  Identify that sign and explain what’s wrong.  Then tell what might be done to correct it.

Math Topic/Concept: Fractions, Measurement

Materials: Rulers, Calculators, And Colored Pencils

Classroom Use: (Introductory/Developmental/Evaluation)

Classroom use comments*:  Discuss requirements.  What is the order of the steps?  How did you decide which sign was incorrect?  Did anyone solve it in a different way?  In the middle your problem did you have to change anything?

Grade: 7-8

Grade Cluster: (MS-Jr.High)

Illinois Goal:  6 and 7

Standard:  6.A.3 and 7.A.3a and 7.B.3

Applied? (1-4):  2

Source: Explain It! Grade 7-8 (Creative Publications) ISBN# 0-7622-1598-4

Answer: C

Strategies Listed:  Computation or Fraction operations.

Solution:  A has 42 squares and 1/3 of 42 = 14
       B has 24 squares and 1/3 of 24 = 8
       C has 20 squares and 1/3 of 20 = 6 2/3

Other solution methods (if any)*:
 

	White	Grey	Letters
Sign A	14	14	14
Sign B	8	8	8
Sign C	4	6	10

 

Extensions or related problems*: Use percents instead of fractions.

Intended rubric or assessment method:  Students are now to create their own sign
· The signs must be composed of equal-sized squares.
· One-fourth of the squares must contain letters.
· One-fourth of the squares must be white.
· One-fourth of the squares must be shaded.
· No pictures can be included in the signs.

Write-up submitted by:   Jenni Robinson and Denise Mann
 
 

James R. Olsen, Western Illinois University
E-mail: jr-olsen@wiu.edu
updated Aug. 20, 2001