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All Saints’ CE Primary School - Maths Written Methods Policy

Children are introduced to the processes of calculation through practical, oral and mental activities. As children begin to understand the underlying ideas they develop ways of recording to support their thinking and calculation methods, use particular methods which apply to special cases, and learn to interpret signs and symbols involved. Over time children use models and images, such as empty lines, to support their mental and informal written methods of calculation. As children’s mental methods are strengthened and refined, so too are their informal written methods. These methods become more efficient and succinct and lead to efficient written methods that can be used more generally. By the end of Year 6 children are well equipped with mental, written and methods that they understand and can use correctly. When faced with a calculation, children are able to decide which method is most appropriate and have strategies to check its accuracy. At whatever stage in their learning, and whatever method is being used, it must still be underpinned by a secure and appropriate knowledge of number facts, along with those mental skills that are needed to carry out the process and judge if it was successful.

The overall aim is that when children leave our school they:  Have a secure knowledge of number facts and a good understanding of the four operations.  Are able to use this knowledge and understanding to carry out calculations mentally and to apply general strategies when using one-digit and two-digit and particular strategies to special cases involving bigger numbers.  Make use of diagrams and informal notes to help record steps and part answers when using mental methods that generate more information than be kept in their heads.  Have an efficient, reliable, compact method of calculation for each operation that children can apply with confidence when undertaking calculations that they cannot carry out mentally.  Use a calculator effectively, using their mental skills to monitor the process, check the steps involved and decide if the numbers displayed make sense.

Mental Methods of Calculation Oral and mental work in maths is essential, particularly so in calculation. Early practical, oral and mental work must lay the foundations by providing children with a good understanding of how the four operations build on efficient counting strategies and a secure knowledge of place value and number facts. Ongoing oral and mental work provides practice and consolidation of these ideas. It must also give the opportunity to apply what they have learned to particular cases and to general cases where children make decisions and choices for themselves. The ability to calculate mentally forms the basis of all methods of calculation and has to be maintained and refined. A good knowledge of numbers or a feel for numbers is the product of structured practice and repetition. It requires an understanding of number patterns and relationships developed through directed enquiry, use of models and images and the application of acquired number knowledge and skills. Secure mental calculation requires the ability to:  Recall key number facts instantly.  Use taught strategies to work out the calculation.  Understand how the rules and laws of are used and applied. Written Methods of Calculation. The framework below sets out progression in written methods of calculation that highlights how children would move from informal methods of recording to expanded methods that are staging posts to a compact written method for each of the four operations.

The aim is that by the end of Key Stage 2, the majority of children should be able to use an efficient written method for each operation with confidence and understanding. This policy promotes the use of what are commonly known as “standard” written methods – methods that are efficient and work for any calculations, including those that involve whole numbers or decimals.

In setting out these aims, the intention is that our school will have a greater consistency in our approach to calculation that all teachers understand and work towards. The challenge for teachers is determining when their children should move on in refinement in the method and become confident and more efficient at written calculation.

Children should be equipped to decide when it is best to use a mental, written or calculator method based on the knowledge that they are in control of this choice as they are able to carry out all three methods with confidence.

Written Methods for of Numbers. The aim is that children use mental methods when appropriate, but for calculations that they cannot do in their heads they use an efficient written method accurately and with confidence. These steps show the stages in building up to using an efficient written method for addition of numbers by the end of Year 6.

To add successfully, children need to be able to:  Recall all addition pairs to 9 + 9 and complements in 10.  Add mentally a series of one-digit numbers such as 5 + 8 + 4.  Add multiples of 10 (such as 60 + 70) or of 100 (such as 600 + 700) using the related addition fact, 6 + 7, and their knowledge of place value.  Carry out column addition and of 2 integers less than 1000 and column addition of more than 2 such integers.  Carry out column addition and subtraction of numbers involving decimals.

Written Methods for Subtraction of Numbers. The aim is that children use mental methods when appropriate, but for calculations that they cannot do in their heads they use an efficient written method accurately and with confidence. These steps show the stages in building up to using an efficient written method for subtraction of numbers by the end of Year 6.

To subtract successfully, children need to be able to:  Recall all addition and subtraction facts to 20.  Subtract by counting up from the smaller number to the larger using number lines.  Subtract multiples of 10 (such as 160 – 70) using the related subtraction fact, (16 – 7) and their knowledge of place value.  Carry out column addition and subtraction of 2 integers less than 1000 and column addition of more than 2 such integers.  Carry out column addition and subtraction of numbers involving decimals.

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286 290 300 700 754 Year 3 Developing – Addition Year 3 Developing - Subtraction Column addition TU with multibase if required. Column subtraction TU with exchanging Ts with multibase if required. Year 3 Secure – Addition Column addition of 2 3-digit numbers. Year 3 Secure - Subtraction Column subtraction of 2 3-digit numbers with exchanging.

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Extend to decimals (same number of decimal places) and adding several numbers (with different numbers of digits).

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Addition – Stage 11 Subtraction – Stage 11 Pencil and paper procedures Extend to numbers with any number of digits and decimals Decomposition with decimals with 1 and 2 decimal places. 124.9 + 115.25 = 242.15 34.14513 3 . 9 8 – 124.9 0 . 5 5 + 117.25 242.15

124.90 + 117.25 242.15 Extend to decimals (either one or two decimal places)

Year 4 Developing – Addition Year 4 Developing – Subtraction Column addition of 2 4-digit numbers. Column subtraction of 2 4-digit numbers.

Year 4 Secure – Addition Year 4 Secure – Subtraction Column addition of decimals to 2 decimal places (d.p.) Column subtraction of decimals to 2d.p

Year 5 Developing – Addition Year 5 Developing – Subtraction Column addition of 2 5-digit numbers. Column subtraction of 2 5-digit numbers.

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Year 2 Developing – Multiplication Year 2 Developing – Division Partitioning up to 50 – no bridging. Up to 50 by partitioning.

Year 2 Secure - Division Year 2 Secure – Multiplication Numerical representation up to 100. Partitioning x by 2, 3 and 5 up to 100.

n Multiplication – Stage 4 Division – Stage 6

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x 20 3 7 140 21 = 161

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Year 3 Developing - Multiplication Year 3 Developing – Division Simple grid method TU x U using x2, x3, x4, x5. Short division by 2, 3, 4 and 5 with carrying.

Year 3 Secure – Multiplication Year 3 Secure – Division Grid method TU x U using x2, x3, x4, x5, x6 and x8. Short division method by 2, 3, 4, 5, 6 and 8 with carrying.

Year 4 Multiplication and Division

Multiply 2 and 3 digits by a single a digit. digits by 3 and 2 Multiply YearSecure 4 tables. all Uusing x HTU using method Simple grid YearDeveloping 4 Method Multiplication Formal Long Multiplication

28 47 4 6x 2

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carrying. with 8, and 7 6, 3, 5, 2, 4, by division method Short YearDeveloping 4 80 10 x 8= 80 Jottings 676 Chunking with Remainders Division Formal division Short (busstop) method Division Short division by any single digit with remainders. with single digit any division by Short 5 x 8= 40 2 x 8= 16 1x 8= Year 4 Secure Secure 4 Year 4 4

groups of 8 of groups groups of 8 = 8640 of groups  4 groups of8 6 / 3 6 /

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