Objective: Students will make collages and use rulers to create scale drawings and find real-life dimensions of objects.
CCSS.Math.Content.7.G.A.1 Solve problems involving scale drawings of geometric figures, including computing actual lengths and areas from a scale drawing and reproducing a scale drawing at a different scale.
Note: students should be familiar with using rulers to find dimensions of two-dimensional objects and finding area of squares and rectangles.
Materials: Large drawing paper, rulers, pencils, home design magazines, scissors, gluesticks
Step One: Introduction
Provide students with a variety of home design magazines (or ask students to bring in their own). Students will have 20 minutes to browse through the magazines and cut out ideas for their own “dream houses” that they would like to build someday.
After students have cut out their pictures, introduce the idea of drawing a floor plan for a house. Encourage students to make a pre-design collage, placing the ideas for their houses in the approximate layout of how they would like their homes to be designed.
After collages are complete, demonstrate how to draw a basic floor plan for a house, using a “bird’s eye” view and drawing the shapes of rooms with flat squares and rectangles (for this activity, you may want to discourage circles unless students are interested in an additional challenge).
Step Two: Creation of Designs and Introduction to Scale
Give students time to draw their floor plans, asking them to label each room and to measure and note dimensions (in inches) of each room. Once your students have drawn their basic floor plans and measured the dimensions of the rooms, stop class for a brief discussion on scale.
Begin the discussion by asking students if they know the dimensions of their homes, and why they think home builders use blueprints. How do home builders know how to make homes the correct size? After students have shared their ideas, introduce a basic scale, drawing it on the board (example 1 inch = 3 feet). Using the sample floor plan drawn for the first portion of the lesson, demonstrate how to use the scale to calculate the actual dimensions of each room. You may want to demonstrate how to make a chart to show the scale in use:
Step Three: Application of Skill
Give students time to apply their scales to find the dimensions of each room shown on their floor plans. Students will fill in their charts accordingly and write the square footage of each room under the label for each room on the blueprints.
Assessment: Collect student’s blueprints or charts and assess the accuracy of students’ calculations.
Extension: Offer students a chance to find the entire square footage of their dream homes, and research the prices of current homes for sale that match the general square footage of the homes they designed for this lesson.