# Lesson 7

Cubic Units of Measure

### Lesson Purpose

The purpose of this lesson is for students to find the volume of rectangular prisms in cubic centimeters, cubic inches, and cubic feet.

### Lesson Narrative

In previous lessons, students used unit cubes with a side length of 1 unit to determine the volume of right rectangular prisms. In this lesson, the units are now a specific unit of measure. In grade 5, students use words, not exponents, when recording the cubic unit of measure, such as “cubic centimeters (cm),” “cubic feet (ft)” or “cubic inches (in).” The exponents in Grade 5 are limited to powers of 10, which will be addressed in a later unit.

In this lesson, students distinguish between different standard unit measures of volume. They examine the distinction between cubic cm, cubic in, and cubic ft. Throughout the lesson, students share their rationale for choosing a unit to measure specific real-world objects and learn the importance of identifying the unit of measure when finding the volume of an object (MP6).

• Representation

### Learning Goals

Teacher Facing

• Find the volume of rectangular prisms with standard units of measure by multiplying the base times the height or multiplying the length times the width times the height.

### Student Facing

• Let’s use different sized cubic units to measure volume.

### Required Materials

Materials to Gather

Materials to Copy

• Info Gap Volume Cards

### Lesson Timeline

 Warm-up 10 min Activity 1 10 min Activity 2 25 min Lesson Synthesis 10 min Cool-down 5 min

### Teacher Reflection Questions

During today's lesson, students described which standard cubic measurement unit they would use to measure the volume of objects that are shaped like rectangular prisms. Consider which objects students see on a regular basis in their communities that are shaped like rectangular prisms. How did you incorporate these objects into the lesson to help students connect their lived experience with their developing math identity?  How can you incorporate these objects into future lessons?

### Suggested Centers

• Five in a Row: Multiplication (3–5), Stage 4: Three Factors (Addressing)
• Capture Squares (1–3), Stage 7: Multiply with 6–9 (Supporting)

### Print Formatted Materials

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