Number Pieces

Reading Time: 2 minutes

If anyone has used dienes before, then they’ll appreciate the idea behind the Number Pieces app. It’s a fantastic tool when teaching addition, subtraction, number bonds, division or multiplication – or even fractions and ratio.

What The Children Do:

The children can drag-and-drop different blocks onto a screen. The blocks vary in size from 100 squares, to strips of 10 and finally 1s. Once the blocks are on-screen, children can split them up or join them together to form smaller or larger numbers respectively.

It’s very straight forward, so I’m going to add some teaching ideas to this page:


Let’s say you’re asking the children the following question 23+ ___ = 100?

screenYou simply allow the children to take a 100 block and break it up into two pieces. One piece has 23 squares and the other piece has 77 and thus 77 is their answer. This is a great way to introduce adding to 100 or number bonds.

You can even take it one step further and ask questions such as 214 + 173 = ?

Allow the children to make 214 using the blocks but then ask them to split it into 200 + 10 + 4 (and then do the same for 173) and then they can add the hundreds, 10s and 1s together to find their answer. The possibilities are endless with this free app.

Do the reverse for subtraction i.e. 100 – 23 = ?


What is 1/4 of 40?

Either give the children a block of 40 squares or ask them to make the block themselves and then ask them to cut it into 4 equal strips. This will help children visualise the fraction because they can literally see that each section is the same size.


What is 84 divided by 12?

Ask the children to create a block of 84 and then to begin counting up in 12s, eventually they’ll have discovered that the answer is 7. You can also reverse this process when teaching multiplication.

These might sound like simple ideas but that’s because I’m predominantly pitching this at KS1, but you can really adapt this anyway you like. For example, instead of saying what is 1/4 of 40 you could say: John has £40 and he spends 3/4 of his money, how much has he spent?

The children then go through the same process of cutting the block into 4 and then add up 3 strips of 10.

I can’t stress how wonderful this tool is.

How It Works:

The children drag-and-drop their block onto the screen and then they can highlight a section (by drawing a ring around it) to pull off and separate the blocks. They can also use the pen tool to write numbers on each block to help them remember the numerical value of the piece. It’s very easy to use and the children should be able to work independently.

Why It’s Good:

This app is great because it’s so visual and can be used across several different topics within maths. You can give children a problem solving lesson and allow them to use the blocks to solve the question or use it to help them counting up (rather than using a number line or their fingers).

It’s a very easy-to-use app that is extremely versatile and is only limited by the power of your imagination! I can’t recommend this highly enough.


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