Subtraction Key Vocabulary: subtract, take away, minus, leave, how many are left? One less two less ten less, how much less is? Difference between, half, halve, tens boundary, hundreds boundary `
Year 1 Number line Year 2 At the start of the year, children consolidate their understanding of the effect of taking away by continuing to count back. However, in Year 2 they will learn to subtract and ‘find the difference’ by counting up from the smaller number to the larger number. Year 3 Empty number line ‐ count up Number line – counting up
Partitioning on a hundred square
Expanded written method: subtract using partitioning – TU – TU This will be developed further in Year 4. See Year 4 for method and explanation, Simple number sentences Children will begin to express subtraction calculations as a number sentence, understanding the meaning of the – sign. Mental Methods
•
•
•
•
Quick recall of number bonds to 10 and 20 Counting on and back from a given number Subtracting 10 from a given number Children can apply these skills to solve spoken word problems too, such as ‘My mum 31 years old and my brother is 26 years younger. How old is my brother?’ Subtraction Key Vocabulary: subtract, take away, minus, leave, how many are left? One/two/ten less, how much less is? Difference between, half, halve, hundred/tens boundary, inverse, decrease Year 4 Expanded written method: subtract using partitioning – TU – TU, HTU – TU Year 5 Expanded written method: subtract using partitioning – TU – TU, HTU ‐ TU Year 6 Column subtraction with decimals Some children will need to continue to use the partitioning method, used in Year 4, until they understand how ‘exchanging’ works and know how to ‘exchange’ accurately. Column subtraction Some children will progress further and will: Begin to use compact column subtraction with support Some children will progress further and will: Column subtraction with decimals Mental Methods
•
•
•
Partitioning – starting with the larger number and subtracting units, then tens, then hundreds. E.g. 352 – 126 = 352 – 6 – 20 – 100 = 226 Counting on – starting with the smaller number and add on to the next ten, then hundred. E.g. 80 – 17 = 17 ‐> 20 ‐>80 = 3 + 60 = 63 Children can apply these skills to solve spoken word problems too, such as ‘My grandma 71 years old and my brother is 49 years younger. How old is my brother?’