| Lesson | Description |
| 1-22 | Introduction to the Symbols + and - |
| 1-22-1 | Addition Facts: Sums 0-5 |
| 1-22-2 | Addition Facts: Sums 0-10 |
| 1-22-3 | Addition Facts: Sums 0-14 |
| 1-22-4 | Addition Facts: Sums 0-18 |
| 1-23 | Addition Facts 1 to 10 |
| 1-23-1 | Addition Facts 1 to 10, Random Order |
| 1-26 | Counting Objects and Counting Forward |
| 1-26-1 | A 100 Problem Addition Facts Assessment |
| 1-26-2 | A 100 Problem Addition Facts Assessment |
| 1-26-3 | A 100 Problem Addition Facts Assessment |
| 1-26-4 | A 100 Problem Addition Facts Assessment |
| 1-26-5 | A 100 Problem Addition Facts Assessment |
| 1-27 | Addition Facts 11 to 15 |
| 1-27-1 | Addition Facts 11 to 15, Random Order |
| 1-28 | Addition Facts 16 to 20 |
| 1-28-1 | Addition Facts 16 to 20, Random Order |
| 1-37 | Addition Facts with the Same Sum |
| 1-38 | Zero and the Sum |
| 1-41 | Adding Two Numbers Up and Down |
| 1-42 | Adding Three Numbers Up and Down |
| 1-46 | The Difference and the Sum Using the Symbols >, <, and = |
| 1-47 | The Fact Families 1 to 10 |
| 1-51 | Two-Digit Addition |
| 2-7 | Introduction to Addition Vocabulary, Addends, Sum, and Equations |
| 2-8 | Using a Number Line to Add and Subtract |
| 2-11 | Finding the Sum of Two Addends |
| 2-12 | Using an Addition Table. Facts, 1 Through 9 |
| 2-16 | Adding Three One-Digit Numbers Vertically |
| 2-17 | Finding the Sums of Two-Digit Numbers |
| 2-22 | Checking Addition Using Subtraction |
| 2-23 | Fact Families 1 - 20 |
| 2-27 | Practice Addition Facts with Missing Addends |
| 2-28 | Two-Digit Addition, Regrouping Ones and Tens |
| 2-31 | Two-Digit Addition, Regrouping Ones and Tens |
| 2-32 | Two-Digit Addition |
| 2-33 | Two-Digit Addition with Regrouping |
| 2-36 | Checking Addition by Reversing the Addends |
| 2-37 | Adding Three Two-Digit Numbers |
| 2-46 | Adding and Subtracting Horizontally |
| 2-47 | Adding and Subtracting Vertically |
| 2-48 | Changing Horizontal Addition to Vertical Addition |
| 2-51 | Building Upon Facts You Already Know. Familiar Patterns. |
| 2-52 | Adding and Subtracting Horizontally |
| 2-76 | Adding Three-Digit Numbers |
| 2-77 | Regrouping Tens |
| 2-78 | Adding Three-Digit Numbers with Regrouping |
| 3-33 | Vertical Addition |
| 3-36 | Mental Math Methods, Addition |
| 3-43 | Adding Four-Digit Numbers |
| 3-52 | Adding and Subtracting Money |
| 3-53 | Mental Math Methods, Thousands |
| 4-11 | Addition: Hundred Thousands Place Value |
| 4-11-1 | Addition: Hundred Thousands Place Value |
| 4-12 | Mental Addition and Subtraction |
| 5-1 | Properties of Addition |
| 5-2 | Variables |
| 5-3 | Opposite Operations, Equations |