Place value in two-digit numbers When you are solving an addition calculation with a two-digit number, you need to think about tens and ones.

Activity: Adding 2-digit numbers Complete this interactive activity to learn more about adding numbers using column addition and then put your knowledge to the test with a quiz.

Conceptually based instruction on place value and two-digit addition and subtraction without regrouping was provided in four first-grade classrooms, and more conventional textbook-based instruction ...

Tape Diagrams: 2-Digit Addition and Subtraction | Grade 2 Special | 2m 20s Your child continues to use tape diagrams as a visual tool to solve word problems.