# Lesson 12

Multiply Multiples of Ten

### Lesson Purpose

The purpose of this lesson is for students to multiply one-digit numbers by multiples of 10.

### Lesson Narrative

The work of this lesson connects to previous work because students have used strategies based on properties of operations to multiply within 100. Now, students extend this work and consider place value to multiply one-digit numbers by multiples of 10. Students complete a problem in context in which they explore how 180 can be grouped into multiples of ten in different ways. Students analyze two strategies for multiplying a single-digit number by a multiple of ten, then complete similar problems using the strategy of their choice. Throughout the lesson the associative property is used as a strategy to think of problems like $$3 \times 60$$ as 18 tens or $$18 \times 10$$.

When students decompose multiples of ten in different ways as a strategy to multiply, they are looking for and making use of structure (MP7).

• Engagement
• MLR8

### Learning Goals

Teacher Facing

• Multiply one-digit whole numbers by multiples of 10 using strategies based on place value and the properties of operations.

### Student Facing

• Let’s multiply one-digit numbers times multiples of 10.

### Required Materials

Materials to Gather

Materials to Copy

• Centimeter Grid Paper - Standard

### Lesson Timeline

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

### Teacher Reflection Questions

Students have used place value in past lessons to add and subtract. In this lesson, how do they begin using place value as a strategy to multiply multiples of 10?

### Suggested Centers

• Compare (1–5), Stage 3: Multiply within 100 (Addressing)
• How Close? (1–5), Stage 5: Multiply to 100 (Addressing)