When you are solving an addition calculation with a two-digit number, you need to think about tens and ones. A place value chart can help you to see the value of each digit in a number. For example, ...

Want to help your first-grader master math? Here are some of the skills your child will be learning in the classroom. Understand place value in one- and two-digit numbers. Understand that in two-digit ...

Addition involves finding the total of two or more numbers or amounts. There are different things you can use to help you add. You can use number lines, place value charts and place value counters.

Korean children's ability to solve addition problems with sums of 10, single-digit addition problems with sums between 10 and 18, and single-digit subtraction problems with minuends between 10 and 18 ...