## Introducing part–whole bar models with your class

Maths lessons should always start with handling and exploring concrete items. Get your class to line objects up as they add and subtract with them. Make sure they can count with accuracy.

When your learners are ready to move on to visual representations, start by keeping one-to-one correspondence with connecting cubes. Learners should see that each cube is a representation of the physical object. Making each part a different colour helps children see that they’re different pieces of the whole.

Next, show the equivalence of the parts to the whole bar. You could, for example, make a ten-cube bar just using red cubes. Or make another bar using eight blue cubes and two yellow ones. Now it’s easier to see that the two bars are equivalent to each other. You can rearrange the bars to make number sentences.

In time, you can draw a bar and display it alongside the cubes to help your learners to see a fully visual representation. Move away from one-to-one correspondence by working with larger amounts.

Learners will soon see that it’s far too cumbersome to use cubes or draw individual squares for a calculation like **25 + ? = 60**. Ask them why you might use a smaller bar to represent a much larger amount.