In this lesson, students recall how to calculate the volume of a cylinder, using informal arguments to compare the volume of a cylinder to the volume of a prism that has an equal height and area of its base. Students start to think about volume in 1-unit layers. This lays a foundation for the informal derivation of the pyramid formula, which will rely on consideration of area of cross-sections. Finally, students apply cylinder volume calculations to a solid of rotation.

Students have opportunities to reason abstractly and quantitatively (MP2) when they compare prism and cylinder volumes.