Lesson 4

Add and Subtract Three-digit Numbers in Different Ways

Lesson Purpose

The purpose of this lesson is for students to add and subtract within 1,000 without composing a ten or hundred using place value understanding, properties of operations, and the relationship between addition and subtraction.

Lesson Narrative

In previous lessons, students used what they know about counting within 1,000 and place value to subtract multiples of 10 and 100 from three-digit numbers. In this lesson, students continue to apply methods they used when adding and subtracting within 100 to add and subtract within 1,000. They also make sense of methods that are represented with equations. In the first activity, they make sense of different methods for subtracting a three-digit number from a multiple of 100. In the second activity, they make sense of methods based on adding by place. Students are invited to try the methods for adding and subtracting that they analyze in this lesson or choose any method that makes the most sense to them. They will continue to analyze and use methods based on adding and subtracting by place in upcoming lessons.

• Action and Expression
• MLR7

Activity 1: Zero Tens and Zero Ones

Learning Goals

Teacher Facing

• Add and subtract numbers within 1,000 using strategies that do not include composing or decomposing tens or hundreds.

Student Facing

• Let’s add and subtract three-digit numbers.

Required Materials

Materials to Gather

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 opportunities are you giving students to reflect on their understanding of the mathematical content?

Suggested Centers

• Five in a Row: Addition and Subtraction (1–2), Stage 6: Add within 100 with Composing (Supporting)
• How Close? (1–5), Stage 3: Add to 100 (Supporting)

Print Formatted Materials

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