There is something mysterious and magical about the idea of "scale." From treasure maps to model railroads, the idea of taking an object or area and shrinking it down to a manageable size appeals to the child in all of us. Tin fact, the 7/8 scale of Disneyland's Main Street is designed to do just that.

You will recall that we took an initial look at this concept way back in Module 1.1 with the Tree Trunk problem. We will now take a deeper look at this concept by creating and analyzing all sorts of scale models.

This unit focuses on the CAHSEE problem:

The actual width (w) of a rectangle is 18 centimeters (cm). Use the scale drawing of the rectangle to find the actual length (l).

A. 6 cm

B. 24 cm

C. 36 cm

D. 54 cm


The major California Mathematics Content standards addressed in this question include:

Number Sense (6th) 1.0 Students solve problems involving fractions, ratios, proportions, and percentages.


In Unit 6.2 Picture This, you will:

  • Deepen your understanding of mathematical concepts in Algebra, including:
    • Using proportional reasoning;
    • Creating and reading scale models; and
    • Determining the scale of an object
  • Develop skills in new instructional strategies, including
    • Using digital camera activities to increase student comprehension of mathematical concepts and problem formulation;
    • Using student-created multimedia presentations to increase student communication and collaboration in mathematics; and
    • Using other classroom technologies to improve teaching and learning of mathematics.