Lesson: Scale drawings

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Lesson Objective

We will be able to determine scale and actual distances

Lesson Plan

Do Now: (5 minutes)
1) Leslie reads 25 pages in 45 minutes. At this rate, how many pages will she read in 60 minutes?

2) Find the GCF of 64ab and 36abc.

3) What is â…œ of 72?

Direct Instruction: (20 minutes)

If I wanted to look at a map of Washington, DC to find where something is located, would it help me if the map was the actual size of the city? Why does that not make sense?

Let’s take a look at the following map (students will have map to put in their composition books). When we are reading a map, what is one of the first things that we need to look at (the scale). What is a scale? How does a scale connect to what we have recently learned about in math? (add definition of scale to notes from student responses)

Scale- the ratio that compares the measurements of the drawing or model to the actual measurements

Ex. (Map in notes) Discuss as a class setting up the proportion

To convert scale:
1) Set up a proportion using the scale and the actual length.    The scale is the numerator.  The actual length is the denominator.
2) Solve for the variable.

Ex. (model ship in notes) Set up proportion as a class

We don’t always need to see a picture or a map to be able to set up the scale

Ex. A map of Bakersfield, CA has a scale of 1 inch to 5 miles. If the city is 5 â…• inches across on the map, what is the actual distance across the city?

Lesson Resources

 scale guided practice 1,577 scale assessment 914 scale notes 1,101