# Lesson 15

More Nets, More Surface Area

### Lesson Narrative

This lesson further develops students’ ability to visualize the relationship between nets and polyhedra and their capacity to reason about surface area.

Previously, students started with nets and visualized the polyhedra that could be assembled from the nets. Here they go in the other direction—from polyhedra to nets. They practice mentally unfolding three-dimensional shapes, drawing two-dimensional nets, and using them to calculate surface area. Students also have a chance to compare and contrast surface area and volume as measures of two distinct attributes of a three-dimensional figure.

### Learning Goals

Teacher Facing

• Draw and assemble a net for the prism or pyramid shown in a given drawing.
• Interpret (using words and other representations) two-dimensional representations of prisms and pyramids.
• Use a net without gridlines to calculate the surface area of a prism or pyramid and explain (in writing) the solution method.

### Student Facing

Let’s draw nets and find the surface area of polyhedra.

### Required Preparation

Copy and cut the blackline master for the Building Prisms and Pyramids activity. Make one copy for every 9 students, so that each student gets one drawing of a polyhedron. Consider assignments of polyhedra in advance.

### Student Facing

• I can calculate the surface area of prisms and pyramids.
• I can draw the nets of prisms and pyramids.

Building On