Describe Prisms and Pyramids Using Algebra

4 teachers like this lesson

Objective

SWBAT describe the relationship between the bases, faces, edges, and vertices of pyramids and prisms using algebraic expressions

Big Idea

Students reinforce algebraic concepts while reviewing (or learning) the terminology for prisms and pyramids.

Lesson Author

Grant Harris

New Orleans, LA

Grade Level

Seventh grade

Subjects

Math

volume (3-D Geom)

Geometry

surface area

algebraic expression

circumference (Determining Measurements)

Standards

7.EE.B.4

Use variables to represent quantities in a real-world or mathematical problem, and construct simple equations and inequalities to solve problems by reasoning about the quantities.

7.G

Geometry

7.G.A

Draw, construct, and describe geometrical figures and describe the relationships between them.

7.G.B.6

Solve real-world and mathematical problems involving area, volume and surface area of two- and three-dimensional objects composed of triangles, quadrilaterals, polygons, cubes, and right prisms.

MP1

Make sense of problems and persevere in solving them.

MP2

Reason abstractly and quantitatively.

MP4

Model with mathematics.

MP8

Look for and express regularity in repeated reasoning.

Lesson Beginning

10 minutes

All Your Bases Are Belong to Us!

Lesson Middle

40 minutes

The first 10-15 minutes of this section are for students to build a prism and a pyramid. I will have nets ready to cut for prisms and pyramids from a triangular base up to an octagonal base. Before students start working, I will explain how to cut and fold the net for best results. It will help to set a timer so that this process, including cleanup, can be finished quickly. Once the shapes are made, students will complete a table to describe the attributes of each shape. I will give about 30 seconds per shape and then ask students to pass the shapes on. Once we’ve agreed on the attributes, I ask students to describe the various parts of an n-sided prism and pyramid (MP2, MP8). I’d like students to grapple with this independently before seeking help. I will ask: What is the relationship between the sides of the base and the lateral faces, vertices and edges? Students will then be asked to find any attribute of a solid when given another piece of information. Example: A certain prism has 12 vertices, how many sides does the base shape have?