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Important update from TheSchoolRun

For the past 13 years, TheSchoolRun has been run by a small team of mums working from home, dedicated to providing quality educational resources to primary school parents. Unfortunately, rising supplier costs and falling revenue have made it impossible for us to continue operating, and we’ve had to make the difficult decision to close. The good news: We’ve arranged for another educational provider to take over many of our resources. These will be hosted on a new portal, where the content will be updated and expanded to support your child’s learning.

What this means for subscribers:

  • Your subscription is still active, and for now, you can keep using the website as normal — just log in with your usual details to access all our articles and resources*.
  • In a few months, all resources will move to the new portal. You’ll continue to have access there until your subscription ends. We’ll send you full details nearer the time.
  • As a thank you for your support, we’ll also be sending you 16 primary school eBooks (worth £108.84) to download and keep.

A few changes to be aware of:

  • The Learning Journey weekly email has ended, but your child’s plan will still be updated on your dashboard each Monday. Just log in to see the recommended worksheets.
  • The 11+ weekly emails have now ended. We sent you all the remaining emails in the series at the end of March — please check your inbox (and spam folder) if you haven’t seen them. You can also follow the full programme here: 11+ Learning Journey.

If you have any questions, please contact us at [email protected]. Thank you for being part of our journey it’s been a privilege to support your family’s learning.

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What is partitioning?

Child solving addition problems - partitioning
Not sure what your child means when they talk about partitioning numbers in maths problems? We explain the method, and how your child will use it.

What is partitioning?

Partitioning is a way of working out maths problems that involve large numbers by splitting them into smaller units so they’re easier to work with. So, instead of adding numbers in a column, like this…

  79
+34
113

…younger students will first be taught to separate each of these numbers into units, like this…

70 + 9 + 30 + 4

…and they can add these smaller parts together. For instance, they can pick out all the tens and work down to single units, making the problem more and more manageable, like this…

70 + 30 + 9 + 4 = 100 + 13 = 113

Why are children taught partitioning?

Children are taught this method before they learn to add numbers in columns. Partitioning gives children a different way of visualising maths problems, and helps them work out large sums in their head. By breaking numbers down into units that are easy for them (and us!) to calculate mentally, they can reach the correct answer without counting out tricky double or triple-digit numbers on their fingers or trying to remember where a decimal point needs to be.

When do children start to partition numbers?

Partitioning is taught in Key Stage 1, to make children aware that a two-digit number is made up of tens and ones. Teachers often use arrow cards for this so that children can physically make a number, such as 24, out of a 20 and a 4.  The idea is that the child lines up the arrows together to make the numbers fit:

Partitioning in addition

These are two commonly used methods for adding larger numbers:

 
A teacher might start teaching children to add two-digit and three-digit numbers in Year 3 by partitioning. The reason for this is that it helps children to mentally add multiples of ten (70 + 50 for example) and multiples of 100 (400 + 800 for example). Children in Year 3 should add also learn to add three-digit numbers using the column method, so your child is likely to encounter both of these methods.

Partitioning in multiplication

Children in Year 3 will also need to multiply two-digit numbers by a one-digit number. They will usually be taught this by partitioning, for example:

37 x 4 =
30 x 4 = 120
7 x 4 = 28
120 + 28 = 148

As children move into Year 4 and 5, they have to start multiplying two two-digit numbers. There are two commonly used methods for this (the grid and column methods); the grid method uses partitioning:

Again, the grid method is used so that children are repeatedly practising multiplying multiples of ten with other numbers, for example: 30 x 20, 30 x 3, 20 x 8, etc. Once teachers are very confident that a child is aware of how to multiply multiples of ten and one hundred, they will often allow a child to move onto the quicker column method.

In Year 6, children need to start calculating with decimals. To make this easier, a teacher may show them how to partition decimals. For example:
3.5 x 7
3 x 7 = 21
0.5 x 7 = 3.5
21 + 3.5 = 24.5