Contents

1. Section A: Develop Fluency with Addition and Subtraction within 10
2. Lesson 1: Sums I Know
   1. Warm-up: Notice and Wonder: Addition Table
   2. 1.1: My Favorite Sum
   3. 1.2: Sums I’ve Got
3. Lesson 2: Relate Counting to Addition
   1. Warm-up: Number Talk: 2 or 3 More
   2. 2.1: More Shake and Spill
   3. 2.2: Are They Both Right?
   4. 2.3: Practice Addition within 10
4. Lesson 3: Are the Expressions Equal?
   1. Warm-up: How Many Do You See: Sums within 10
   2. 3.2: Are Both Sides Equal?
5. Lesson 4: Sums of 10
   1. Warm-up: True or False: Equal Expressions
   2. 4.2: All The Ways To Make 10
   3. 4.3: Centers: Choice Time
6. Lesson 5: Find the Difference
   1. Warm-up: Number Talk: Missing Value Within 10
   2. 5.1: Different Ways to Find the Difference
   3. 5.2: Subtraction Number Strings
   4. 5.3: The Value of the Difference
7. Lesson 6: Story Problems within 10
   1. Warm-up: Notice and Wonder: Han's Cup
   2. 6.1: A Shake and Spill Story Problem
   3. 6.2: Shake and Spill Story Problems
   4. Section A Summary
8. Lesson 7: Center Day 1
   1. 7.2: Centers: Choice Time
   2. Section A Practice Problems
9. Section B: Add and Subtract using Ten as a Unit
10. Lesson 8: Ten as a Unit
    1. Warm-up: Which One Doesn’t Belong: Groups of 10
    2. 8.2: Building Teen Numbers
11. Lesson 9: Addition With a Ten
    1. Warm-up: Notice and Wonder: Teen Numbers
    2. 9.1: Make It: Teen Numbers and 10-Frames
    3. 9.2: Equations With a Ten
12. Lesson 10: Addition and Subtraction with a Ten
    1. Warm-up: Number Talk: A Ten and Some Ones
    2. 10.1: Story Problems With a Ten
    3. 10.2: Related Equations
13. Lesson 11: Add to a Teen Number
    1. Warm-up: True or False: Teen Numbers
    2. 11.1: Rock Collection
    3. 11.2: Write Equations: Adding on to Teen Numbers
    4. 11.3: Centers: Choice Time
14. Lesson 12: Subtract From a Teen Number
    1. 12.1: Noah’s Collection
    2. 12.2: Addition and Subtraction Equations with Teen Numbers
15. Lesson 13: More Story Problems with Teen Numbers
    1. Warm-up: Number Talk: Add Ones
    2. 13.1: Sitting or Standing
    3. 13.2: Solve Story Problems and Compare Methods
    4. 13.3: Centers: Choice Time
    5. Section B Summary
16. Lesson 14: Center Day 2
    1. Warm-up: True or False: Expressions on Both Sides
    2. 14.2: Centers: Choice Time
    3. Section B Practice Problems
17. Section C: Add within 20
18. Lesson 15: Solve Story Problems with Three Numbers
    1. Warm-up: How Many Do You See: 10-frames
    2. 15.1: Louis Agassiz Fuertes’s Birds
    3. 15.2: Fuertes’s Bird Cards
19. Lesson 16: Add Three Numbers
    1. Warm-up: Number Talk: Related Expressions
    2. 16.1: Match Expressions
    3. 16.2: Is the Equation True?
    4. 16.3: Write Expressions
20. Lesson 17: Make 10 to Add
    1. Warm-up: How Many Do You See: Double 10-frames
    2. 17.1: The 9 Plus Game
    3. 17.2: Clare’s Birds
21. Lesson 18: Patterns in Addition
    1. Warm-up: How Many Do You See: More Double 10-frames
    2. 18.1: Expression Match
    3. 18.3: Centers: Choice Time
22. Lesson 19: Methods for Addition Within 20
    1. Warm-up: Number Talk: Related Expressions
    2. 19.1: Lin, Han, and Kiran Add
    3. 19.2: How Did You Add?
23. Lesson 20: A Trip to the Zoo
    1. Warm-up: Number Talk: Using 10 + \boxed{\phantom{4}}
    2. 20.1: How Many Reptiles?
    3. 20.2: Zoo Exhibits
    4. Section C Summary
24. Lesson 21: Center Day 3
    1. Warm-up: What Do You Know About 20?
    2. Section C Practice Problems
25. Section D: Subtract within 20
26. Lesson 22: Subtract from Teen Numbers
    1. Warm-up: Number Talk: Subtract from a Teen Number
    2. 22.1: Subtraction Methods
    3. 22.2: Number Card Subtraction
27. Lesson 23: Use a Ten to Subtract
    1. Warm-up: Number Talk: Subtract to Make 10
    2. 23.1: Number Card Subtraction with 10-frames
    3. 23.2: Diego and Andre Find the Difference
28. Lesson 24: Relate Counting to Addition and Subtraction
    1. 24.1: Different Ways to Subtract
    2. 24.2: Find the Number That Makes Each Equation True
29. Lesson 25: How Do You Want to Subtract?
    1. 25.1: Choose Your Own Subtraction Method
    2. 25.2: Solve Story Problems
30. Lesson 26: What’s the Story?
    1. Warm-up: Number Talk: Subtract 10 or More
    2. 26.1: Solve Related Story Problems
    3. 26.2: More Story Problems
    4. Section D Summary
31. Lesson 27: Center Day 4
    1. Warm-up: Number Talk: Subtract 10
    2. 27.2: Introduce Compare, Add and Subtract Within 20
32. Lesson 28: Around the Room
    1. Warm-up: Notice and Wonder: Counting Things in the Classroom
    2. 28.1: Writing Classroom Story Problems
    3. 28.3: Poster Gallery Walk
    4. Section D Practice Problems
33. Glossary
34. Attributions
    1. Image Attributions
35. Citations
36. Notes
37. Notes