This Problem Set is a part of the Lesson 15, Unit 1, Grade 6. This lesson further develops students' ability to visualize the relationship between nets and polyhedra and their capacity to reason about surface area. 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.