Addition and subtraction with small friend strategy.

Addition and subtraction with small and big friend strategy.

Addition and subtraction and multiplication 2-digit numbers with 1-digit number.

Addition and subtraction, multiplication 3-digit numbers with 1-digit number and division 3 digit numbers with 1-digit number.

Addition and subtraction, multiplication and division 4-digit numbers with 1-digit number.

Addition and subtraction, multiplication and division 2-digit numbers with 3 -digit numbers.

Addition and subtraction, multiplication and division 3-digit numbers with 4-digit numbers.

Addition and subtraction, multiplication an division 4-digit numbers with 6-digit numbers.

Addition and subtraction, multiplication an division 7-digit numbers with 6-digit numbers.