# Understanding the Unit Cube Concept: Math Lesson Plan for Grade 5

Identify a “unit cube” as a cube with side lengths of one unit and with a volume of one cubic unit. Scroll to the end of this article to download a copy of this lesson plan.

**Lesson Objective:** The lesson is aligned to the Common Core State Standards for Mathematics – 5MD.3a and b Geometric Measurement – Recognize volume as an attribute of solid figures and understand concepts of volume measurement.

**Materials Required:** “unit cubes”

## Identifying Measurement of Rectangular Figures Using a Unit Cube

Look at the unit cube in the image above. Each side of the cube measures 1 unit. A cube with each side measuring 1 unit is called a unit cube. A unit cube has a volume of one cubic unit.

A unit cube can be used to measure volume.

To measure the volume of a rectangular figure, without gaps or overlaps pack the rectangular figure with the unit cubes.

Look at the rectangular figure in the second image above. The rectangular figure is packed with 6 unit cubes. The volume of the rectangular figure is 6 cubic units.

Look at the rectangular figures above. Count the number of unit cubes packed in the rectangular figure.

- How many unit cubes are packed in the rectangular figure shown in Figure 1? What is the volume in cubic units?
- How many unit cubes are packed in the rectangular figure shown in Figure 2? What is the volume in cubic units?

**Answers:**

- 12 unit cubes, 12 cubic units
- 18 unit cubes, 18 cubic units

## Individual or Group Work

Look at the figures above. Count the number of unit cubes packed in the figure.

- How many unit cubes are packed in Figure 3? What is the volume in cubic units?
- How many unit cubes are packed in Figure 4? What is the volume in cubic units?
- How many unit cubes are packed in Figure 5? What is the volume in cubic units?

**Answers:**

- 15 unit cubes, 15 cubic units
- 14 unit cubes, 14 cubic units
- 8 unit cubes, 8 cubic units

Students should be able to count the number of unit cubes used to fill rectangular figures to determine the volume of the figures.

Download a copy of the lesson.

## This post is part of the series: Finding Volume Measurement With Unit Cubes

This collection of fifth grade lesson plans focuses on teaching the concept of the unit cube and how it can be used to develop volume measurement formulas. All lessons meet Common Core objectives.