# Lesson 1

How Many Groups?

### Lesson Purpose

The purpose of this lesson is for students to solve “how many groups?” problems in a way that makes sense to them.

### Lesson Narrative

In a previous unit, students were introduced to multiplication. They interpreted products as the total number of objects in a given number of groups of equal size. Students represented groups of equal size using drawings, tape diagrams, and arrays.

The purpose of this lesson is to introduce problems that involve putting objects into groups of equal size, starting with “how many groups?” problems. Even though the structure of the problems suggests division, students may use their understanding of multiplication or any strategy that makes sense to them to solve the problems. If students use connecting cubes, encourage them to draw a picture to match their work. In the lesson synthesis, students have a chance to think about how they would define division. The definition and symbol for division will be introduced in subsequent lessons.

• Representation
• MLR8

### Learning Goals

Teacher Facing

• Solve “how many groups?” problems in a way that makes sense to them.

### Student Facing

• Let’s represent and solve problems.

### Required Materials

Materials to Gather

Building Towards

### Lesson Timeline

 Warm-up 10 min Activity 1 20 min Activity 2 15 min Lesson Synthesis 10 min Cool-down 5 min

### Teacher Reflection Questions

In this lesson, students are introduced to division for the first time. How is their understanding of multiplication influencing and supporting how they solve division problems?

### Suggested Centers

• Rectangle Rumble (3–5), Stage 2: Factors 1–5 (Supporting)
• Five in a Row: Multiplication (3–5), Stage 2: Factors 1–9 (Supporting)