Scale Drawings

Overall Lesson Time: 1 Hour

Image: Scale Drawings

Why this lesson is awesome! How far is it to Grandma’s house? It looks like 2 inches on the map…

Objective: Students will use proportional relationships to calculate scale and actual measurements. (Standard 7.G.1)

1. Launch
Indicated Time Allotment: 5-10 minutes

Opener: As students enter the room, they will immediately pick up and begin working on the opener (Resource: Scale Drawings Opener, Smartboard). Please see my instructional strategy clip for how openers work in my classroom (Process for openers). This method of working and going over the opener lends itself to allow students to construct viable arguments and critique the reasoning of others, which is mathematical practice 3. See my video, MP3, for more!
Learning Target: After completion of the opener, I will address the day’s learning targets to the students. In today’s lesson, the intended target is, “I can apply proportional reasoning to solve scale drawing problems.” Students will jot the learning target down in their agendas (our version of a student planner, there is a place to write the learning target for every day).

Resources: Scale Drawings Opener, Scale Drawings Smartboard

2. Explore

Indicated time allotment: 50-55 minutes

Connect Four: The middle part of this lesson is going to begin practice review on Scale Drawings, using a Connect Four game template. This practice activity brings in a variety of ways scale drawings may appear in a question – scale factor, missing dimensions, enlargement, etc. I will conduct this activity boys versus girls – and move students seats to accommodate that grouping. Students will work the problem out on their own, and then discuss the answers/methodology with their team. When I call time, a student of my choosing will go to the board and solve the problem. If the student correctly solves he/she will place a checker on the board, if not, I will turn the question over to the other team. Since I am conducting the review as a challenge, it will require students to make sense of the problems and persevere in solving them, which is an application of mathematical practice 1 (see video MP1). I don’t like to be accused of “cheating” for a group, so I save my help and expertise until AFTER I groups have attempted the problem at the board. The questions used in the activity also require students to reason abstractly – having to develop an equation based on the words that they see, which is an implementation of mathematical practice 2 (see video MP2).
Sample Test Questions: I will stop the connect four activity either when a group wins, or 15 minutes before the end of class, and have students begin the sample test questions (Scale Drawings Sample Test Questions). I find it extremely important that students have an opportunity to dissect examples of test questions, as often it is the wording, not the content, that trips students up. It will be extremely important that students pay close attention to their units with these problems, as living 3 miles from grandma is very different from living 3 inches from her! This brings in mathematical practice 6, attention to precision (MP6).

Resources: Scale Drawings Sample Test Questions

3. Summarize

Indicated time allotment: 1-2 minutes

Table Discussion: Scale Drawings Summary Narrative, Instructional Strategy – Table Discussion