To get an internal sense of how numbers relate to each other, students can practice working with number lines.

Save guides, add subjects and pick up where you left off with your BBC account. You can add or subtract numbers in lots of different ways. You can use number lines, number bonds, fact families, 10 ...

There are lots of different tools that help you to do mental addition and subtraction. Remember, it doesn't have to be done entirely in your head, you can still use a pencil and paper to help.