Explaining how we teach mathematics, and what you can do to help your child become a confident mathematician. Addition and subtraction

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572 is partitioned into 500 and 70 and  A vital skill.  It is understanding that what each digit is worth is dependent on its position in a number.  Visually supported with use of arrow cards, digit cards and base blocks. Place value and partitioning Using base blocks

Place value grid  Then adding and subtracting 1, 10 and 100. e.g. spreadsheet or PV Chart v8.exePV Chart v8.exe 1 or 10 more or less bingo

Hundred square

Ordering Being able to put numbers in order and place them on a number line. Ordering numbers: Number line

Which number is bigger? Which number is smaller? Using the symbols: is smaller than

Identifying the sequence and adding to it. This includes completing dot to dot pictures and making patterns with coloured beads then goes on to completing number sequences such as: a) ___ ___ b) ___ ___ ___ c) ___ ___ Children also need to be able to explain what the sequence/pattern is e.g. a) adding 2, b) subtracting 5 c) subtracting 0.5 We use a counting stick to practise counting in sequences.

Need to know the multiples of 10 and 100 Multiples of 10 are: etc. Which multiple of 10 is 65 between? 65 Which multiple of 10 is 65 nearest? rounds to 70 Post box sorting

Estimating Rounding to estimate what the answer will be near. How many sweets? How many shells? rounds to = 120 so the answer must be near 120

Adding Key stage 1: Start with the biggest number first Count on Use a number line Any written work is done horizontally =

Number bonds We can’t emphasise enough the need for children to confidently know their number facts before they progress to more formal written methods. addition and subtraction bonds for totals up to 10 addition and subtraction bonds for totals up to 20 doubles of all numbers up to 10 and then 20 addition and subtraction bonds with multiples of 10 for totals up to 100 addition and subtraction bonds with multiples of 5 for totals up to 100 These facts will enable them to carry out the more formal methods of addition and subtraction with confidence. Hit the button Triangular cards

Adding two digit numbers using informal methods = ( ) + (3 + 2) = 55 Easy sums: = 50 Then = ( ) = 52 and finally = ( ) + (5 + 7) = 62 The aim is that, eventually children will be able to add two 2 digit numbers mentally. Adding with arrow cards

We introduce more formal written methods in stages. First this: = = = = 74 Then this: Then this: Expanded addition

Subtracting Key stage 1: Any written work is done horizontally Count back Use a number line The difference between 7 and 4 is 3 7 – 4 =

Subtraction After lots of visual, practical and mental subtraction work with single digit numbers including use of a number line and use of relevant language such as difference between, minus, how many less is?... how many less than?..., subtract, take, take away etc. children learn to subtract larger numbers. We begin to teach more formal methods using partitioning. 67 – 23 = = 44

Because we can’t take 7 from 3 we re-partition, moving 10 across = – – – Finally we move to the more compact method, when we feel children are ready for this. For some children the final compact method will be difficult and they will continue to use informal methods into year 6. This compact method is known as 'decomposition‘. They will progress to using bigger numbers and decimals Decomposition

Thank you for reading this. We hope you find it useful. Wizard number What is the Number?