# Lesson 4

Standard Algorithm: One-digit and Multi-digit Numbers with Composing

### Lesson Purpose

The purpose of this lesson is for students to use the standard algorithm to multiply up to five-digit numbers and one-digit numbers.

### Lesson Narrative

In grade 4, students interpreted the standard algorithm for multiplication and compared it to a partial products algorithm to multiply up to four-digit numbers and one-digit numbers. In this lesson, students extend their understanding of the standard algorithm to multiply up to five-digit numbers and one-digit numbers, including problems where one or more new units are composed. This is the first in a series of lessons to support students in developing fluency using the standard algorithm to multiply multi-digit numbers.
• Representation

### Learning Goals

Teacher Facing

• Use the standard algorithm to multiply up to five-digit numbers by one-digit factors, including composing new units.

### Student Facing

• Let’s use the standard algorithm to multiply one-digit numbers and multi-digit numbers.

### 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

What evidence do you see that your students are applying what they learned about partial products to make sense of the standard algorithm?

### Suggested Centers

• Number Puzzles: Multiplication and Division (4–5), Stage 2: Multi-digit Factors (Addressing)

### Print Formatted Materials

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