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PROGRESSION IN CALCULATIONS MULTIPLICATION Mental Skills Vocabulary • Recognise the size and position of numbers • Count on in steps of 2, 5, 10 • Double numbers up to 10 • Recognise multiplication as repeated addition • Quick recall of multiplication facts • Use known facts to derive associated facts • Multiply by 10, 100, 1000 and understand the effect • Multiply by multiples of 10 MULTIPLICATION Children are taught to understand multiplication as repeated addition and scaling. It can also describe an array. 2x4= Each child has two eyes. How many eyes do four children have? 2 + 2 + 2 + 2 5x3= There are 5 cakes in a pack. How many cakes in 3 packs? Use pictures and equipment to count 2s. Dots or tally marks are often drawn in groups. This shows 3 groups of 5. 2x4= A chew costs 2p. How much do 4 chews cost? Drawing an array gives children an image of the answer. It also helps develop the understanding that 2 x 4 is the same as 4 x 2. 6x4= There are 4 cats. Each cat has 6 kittens. How many kittens are there altogether? Children can represent arrays on a numberline counting on in equal steps. This shows 6 jumps of 4. 6x4= This can be done on an unnumbered number line, reinforcing links with multiplication and repeated addition. This shows 4 jumps of 6. 0 6 12 18 24 13 x 4 = There are 13 biscuits in a packet. How many biscuits in 7 packets? (+40) (+12) 10 x 4 0 3x4 40 52 When numbers get bigger, it is inefficient to do lots of small jumps. Partition 13 in to tens and units (10 and 3). This gives you two jumps (10 x 4 and 3 x 4). 13 x 4 = This can also be represented using place value apparatus and partitioning. Each number is multiplied, and the answers added together. 13 x 4 = When children have secured their understanding through the use of equipment they will be able to record it as the grid method. A secure understanding as to what is happening when we multiply larger tens numbers is crucial and may also be supported by apparatus. 23 x 4 = 33 x 14 = Multiplying two digit x two digit. Partition the numbers and multiply each part. Add across the rows, and then add those answers together. 56 x 27 = As place value knowledge becomes secure, the standard written method may be used. Also known as long multiplication. Progression in Calculations January 2012