Unit 3

Adding and Subtracting within 20

Section A

Develop Fluency with Addition and Subtraction within 10

Sums I Know

Let’s see which sums within 10 we know.

Relate Counting to Addition

Let’s add within 10.

Are They Equal?

Let’s think about how different expressions can have the same value.

Sums of 10

Let’s find all the ways to make 10.

Find the Difference

Let’s find differences within 10.

Story Problems within 10

Let’s solve story problems.

Center Day 1

Let’s play games to practice adding.

Section A Practice Problems

Section A

Develop Fluency with Addition and Subtraction within 10

Sums I Know

Let’s see which sums within 10 we know.

Relate Counting to Addition

Let’s add within 10.

Are They Equal?

Let’s think about how different expressions can have the same value.

Section B

Add and Subtract Using Ten as a Unit

Ten as a Unit

Let's explore teen numbers.

Addition with a Ten

Let's use a ten to make teen numbers.

Addition and Subtraction with a Ten

Let's add and subtract with teen numbers.

Add to a Teen Number

Let’s add to teen numbers.

Subtract from a Teen Number

Let’s subtract and add within 20.

Center Day 2

Let’s play games to practice adding and subtracting.

Section B Practice Problems

Section B

Add and Subtract Using Ten as a Unit

Ten as a Unit

Let's explore teen numbers.

Addition with a Ten

Let's use a ten to make teen numbers.

Addition and Subtraction with a Ten

Let's add and subtract with teen numbers.

Section C

Add within 20

Solve Story Problems with Three Numbers

Let’s solve story problems with 3 numbers.

Add 3 Numbers

Let’s add 3 numbers.

Make 10 to Add

Let’s look for patterns and think about making 10 as we add.

Patterns in Addition

Let’s look for and use patterns to help us add within 20.

Methods for Addition within 20

Let’s add within 20.

A Trip to the Zoo

Let’s solve story problems.

Center Day 3

Let’s play games where we add.

Section C Practice Problems

Section C

Add within 20

Solve Story Problems with Three Numbers

Let’s solve story problems with 3 numbers.

Add 3 Numbers

Let’s add 3 numbers.

Make 10 to Add

Section D

Subtract within 20

Subtract from Teen Numbers

Let’s subtract from a teen number.

Use a Ten to Subtract

Let’s use 10 to help us subtract.

Relate Counting to Addition and Subtraction

Let’s subtract by counting on or taking away.

How Do You Want to Subtract?

Let’s use subtraction methods that work for the numbers in a problem.

What’s the Story?

Let’s solve story problems.

Center Day 4

Let’s play games to practice addition and subtraction.

The Garden

Let’s write and solve story problems.

Section D Practice Problems

Section D

Subtract within 20

Subtract from Teen Numbers

Let’s subtract from a teen number.

Use a Ten to Subtract

Let’s use 10 to help us subtract.

Relate Counting to Addition and Subtraction

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Assessment Access

Adding and Subtracting within 20

Develop Fluency with Addition and Subtraction within 10

Sums I Know

Relate Counting to Addition

Are They Equal?

Sums of 10

Find the Difference

Story Problems within 10

Center Day 1

Section A Practice Problems

Develop Fluency with Addition and Subtraction within 10

Sums I Know

Relate Counting to Addition

Are They Equal?

Add and Subtract Using Ten as a Unit

Ten as a Unit

Addition with a Ten

Addition and Subtraction with a Ten

Add to a Teen Number

Subtract from a Teen Number

More Story Problems with Teen Numbers

Center Day 2

Section B Practice Problems

Add and Subtract Using Ten as a Unit

Ten as a Unit

Addition with a Ten

Addition and Subtraction with a Ten

Add within 20

Solve Story Problems with Three Numbers

Add 3 Numbers

Make 10 to Add

Patterns in Addition

Methods for Addition within 20

A Trip to the Zoo

Center Day 3

Section C Practice Problems

Add within 20

Solve Story Problems with Three Numbers

Add 3 Numbers

Make 10 to Add

Subtract within 20

Subtract from Teen Numbers

Use a Ten to Subtract

Relate Counting to Addition and Subtraction

How Do You Want to Subtract?

What’s the Story?

Center Day 4

The Garden

Section D Practice Problems

Subtract within 20

Subtract from Teen Numbers

Use a Ten to Subtract

Relate Counting to Addition and Subtraction

Have a correction or suggestion?

Unit 3 Resources

Sums of 10

Find the Difference

Story Problems within 10

Center Day 1

Add to a Teen Number

Subtract from a Teen Number

More Story Problems with Teen Numbers

Center Day 2

Patterns in Addition

Methods for Addition within 20

A Trip to the Zoo

Center Day 3

How Do You Want to Subtract?

What’s the Story?

Center Day 4

The Garden