Lesson 3: From Area to Volume

Getting Started

Now that you know what a rectangular prism is, you're ready to learn about volume. You've reviewed that perimeter measures the distance around a 2D shape and area is the amount of space inside a 2D shape. Volume is the amount of space a 3D shape takes up. For example, imagine that you want to buy a storage box to keep under your bed. You would need to know the box's length, width, and height in order to determine how much space it takes up. You would the use length, width, and height measurements to figure out the box's volume.

While you can figure out the volume for all sorts of 3D shapes, during this unit, you're going to focus on working with the volumes of rectangular prisms.

Stuff You Need

  • centimeter cubes (kit)* (Activity 2 - optional)
  • fine point dry-erase markers (kit)
  • laminated isometric dot sheet (kit)
  • ruler (kit)

* - denotes an optional material that may or may not be needed

Ideas to Think About

  • What is volume?
  • How are volume and area related?

Things to Know

  • Volume: the amount of space a 3D shape takes up
  • Cubic units: the units used when measuring volume
  • Isometric drawing is a way to draw 3D shapes on a 2D surface, like paper.


  • Recognize volume as an attribute of solid figures and understand concepts of volume measurement
  • Create rectangular prisms using cubes

Introducing the Lesson

During this lesson, your child is going to learn what volume is and how it relates to area. Then, he will practice drawing rectangular prisms.

MATERIALS NOTE: The isometric dot sheet used in this and future lessons in this unit can be downloaded from the following web link. You can laminate the sheet or place it in a plastic page protector for your child to use with a thin-tipped dry-erase marker. If you prefer, you can instead print out several paper copies for your child to use in this lesson with a pencil.
Web Link