Key ideas in the Numeracy Strategy Mental methods of calculation are stressed Standard written calculations are delayed until pupils have fundamental ideas about place value and have a repertoire of mental calculation strategies

How would you work out … = = 68 – 34 = 101 – 59 =

Addition At Key Stage 1 ‘sums’ are usually written horizontally Number lines are often used to support informal methods and help build up imagery =

Addition continued… Children are introduced to ‘partitioning’ Early stage: = = = = 65 Then: Lastly:

Subtraction at KS1 Children use practical objects to carry out ‘take away’ and ‘find the difference’ Number lines and 100 squares provide important models Difference ITP Counting on and counting back 25 – 326 – 21 _______________

Subtraction at KS2 Children are taught to subtract by finding the difference between the two numbers. This method involves counting on from the smaller to the larger number and is called ’complementary addition’ 85 – 57 _85 57 ____________________________ 3 (60) 25 (85) 28

Subtraction with larger numbers 326 – 178 ______________________ (200) 126 (326) 148

Subtraction at KS2 Finding the difference continues to be an important informal method When children are ready, they are introduced to ‘decomposition’, which involves partitioning 245 – 123 = – Leading to:

Multiplication Early work on multiplication involves images of groups and arrays: Multiplication Facts ITP Next children use partitioning for calculations: 26 x 7 = 20 x 7 = x 7 = x 7 = 182

Multiplication – the ‘grid method’ 7 x 23 = 161 Multiplication grid x

Multiplication - continued Another method of recording is taught to children who are ready x 6 x 52

Division Early work on division involves sharing and grouping Grouping Next children are encouraged to understand division as building up multiples (chunking) 84 ÷ 6 = _________________________________

Division – the ‘chunking method’ 305 ÷ 7 = (estimate: 40 x 7= 280 so the answer is a bit more than 40) (40 x 7) ( 3 x 7) ÷ 7 = 43 r 4

Division continued Children who are ready, are taught another method of recording 267 ÷ 8 = ____ 8) 267

In conclusion … Children are always encouraged to think which is the most appropriate and efficient method for the numbers involved Mental methods should be the first resort