Lesson objective: Find the surface area of three dimensional figures from their nets.

This lesson helps to build the procedural skill of decomposing a net into shapes that have area formulas. Highlighting the shapes within nets is used here because it supports the concept that nets of rectangular and triangular prisms and pyramids are composed entirely of rectangles and triangles. This work develops students' understanding that nets of three dimensional figures allow us to see the faces of the figure and how the sum of the area of the faces results in the surface area.

Students engage in Mathematical Practice 4 (Model with Mathematics) as they use nets of pyramids and prisms to make connections between two dimensional shapes and three dimensional figures. Students also engage in Mathematical Practice 7 (Look for and Make Use of Structure) as they decompose nets into shapes that have area formulas to determine surface area.

**Key vocabulary: **

- area
- net
- square units
- surface area
- three dimensional figure
- two dimensional shape