1.1. Number & place value
1.1.1. Mixed operations
1.1.2. Counting Up to 99
1.1.3. Counting Up to 999
1.1.4. Skip Counting
1.1.5. Numerals and Number Names
1.1.6. Number lines
1.1.8. Place Values and Face Values
1.1.9. Roman Numerals I, IV, X, L
1.1.10. Even and Odd
1.1.11. Addition
1.1.12. Subtraction
1.1.12.1. Subtract Two One-Digit Numbers
1.1.12.3. Subtraction of Two Numbers
1.1.12.3.1. Subtract Two Two-Digit Numbers
1.1.12.3.1.1. Subtract Two Two-Digit Numbers (Without Borrowing)
1.1.12.3.1.2. Subtract Two Two-Digit Numbers (With Borrowing)
1.1.12.3.2. Subtract Two Three-Digit Numbers
1.1.12.4. Forming Numbers Using Subtraction
1.1.12.5. Write subtraction number sentence
1.1.14. Multiplication
1.1.15. Division
1.4. Patterns and algebra