Unit 1, Lesson 10
What Is Surface Area?
Accelerated 6
Preparation
Lesson Narrative
This lesson introduces students to the concept of surface area. They use what they learned about the area of rectangles to find the surface areas of prisms with rectangular faces.
Students begin by exploring surface area in concrete terms, by thinking about the number of square sticky notes it would take to cover a filing cabinet. First, they make an estimate, and then they think about what information is needed to calculate the actual number of sticky notes. Because no techniques are given, students need to make sense of the problem and persevere in solving it (MP1). As they analyze the situation, think about the problem in context, and consider the mathematics strategies that they know, students practice modeling with mathematics (MP4).
Students learn that "surface area" (in square units) is the number of unit squares it takes to cover all the faces of a three-dimensional figure without gaps or overlaps.
Later in the lesson, students determine the surface area of rectangular prisms that are built from snap cubes.
- Calculate the surface area of a rectangular prism and explain (orally and in writing) the solution method.
- Comprehend that the term “surface area” (in written and spoken language) refers to how many square units it takes to cover all the faces of a three-dimensional object.
Let’s cover the surfaces of some three-dimensional objects.
Required Materials
Activity 3
Required Preparation
Build several rectangular prisms that are each 2 cubes by 3 cubes by 5 cubes for the Cool-down.
Prepare 12 cubes per student and extra copies of isometric dot paper.