To add two-digit numbers, you need to think about place value. You start by adding up how many ones you have. If you have more than 10 ones, you can put a group of ten into the tens column.

Let’s put this old misconception to bed: The cognitive science about math learning indicates that, yes, students do need to develop fluency with their multiplication tables and single-digit ...

Learn how to add two-digit numbers in this Year 2 article from BBC Bitesize. ... When you are solving an addition calculation with a two-digit number, you need to think about tens and ones.