 Lesson plan

# Lesson 8: Scale Drawings and Maps

teaches Common Core State Standards MP1 http://corestandards.org/Math/Practice/MP1
teaches Common Core State Standards MP4 http://corestandards.org/Math/Practice/MP4
teaches Common Core State Standards MP2 http://corestandards.org/Math/Practice/MP2
teaches Common Core State Standards 7.G.A.1 http://corestandards.org/Math/Content/7/G/A/1

# Lesson 8: Scale Drawings and Maps

This lesson is optional. In this lesson, students apply what they have learned about scale drawings to solve problems involving constant speed (MP1, MP2). Students are given a map with scale as well as a starting and ending point. In addition, they are either given the time the trip takes and are asked to estimate the speed or they are given the speed and asked to estimate how long the trip takes. In both cases, they need to make strategic use of the map and scale and they will need to estimate distances because the roads are not straight.

In the sixth grade, students have examined many contexts involving travel at constant speed. If a car travels at 30 mph, there is a ratio between the time of travel and the distance traveled. This can be represented in a ratio table, or on a graph, or with an equation. If $$d$$ is the distance traveled in miles, and $$t$$ is the amount of time in hours, then traveling at 30 mph can be represented by the equation $$d=30t$$. Students may or may not use this representation as they work on the activities in this lesson. But they will gain further familiarity with this important context which they will examine in greater depth when they study ratios and proportional reasoning in grade 7, starting in the next unit.

Lesson overview

• 8.1 Warm-up: A Train and a Car (5 minutes)
• 8.2 Optional Activity: Driving on I-90 (15 minutes)
• There is a digital applet in this activity.
• 8.3 Optional Activity: Biking through Kansas (10 minutes)
• Includes "Are you Ready for More?" extension problem
• Lesson Synthesis
• 8.4 Cool-down: Walking Around the Botanical Garden (5 minutes)

Learning goals:

• Justify (orally and in writing) which of two objects was moving faster.
• Use a scale drawing to estimate the distance an object traveled, as well as its speed or elapsed time, and explain (orally and in writing) the solution method.

Learning goals (student facing):

• Let’s use scale drawings to solve problems.

Learning targets (student facing):

• I can use a map and its scale to solve problems about traveling.

Required materials:

• geometry toolkits

Required preparation:

Glossary:

• Access the complete Grade 7 glossary.

Standards

• This lesson builds on the standards: CCSS.6.NS.B.2MS.6.NS.2CCSS.6.RP.A.3.bMS.6.RP.3bMO.6.NS.B.2MO.6.RP.A.3b
• This lesson builds towards the standard: CCSS.7.RP.ACCSS.7.RP.A.2.bMS.7.RP.2bMO.7.RP.A.2b

IM 6–8 Math was originally developed by Open Up Resources and authored by Illustrative Mathematics, and is copyright 2017-2019 by Open Up Resources. It is licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0). OUR's 6–8 Math Curriculum is available at https://openupresources.org/math-curriculum/.