Represent Numbers
Representing numbers bridges the gap between abstract mathematical concepts and tangible understanding for Reception and Year 1 pupils. When children can show 47 using base-10 blocks, tally marks, or written words, they develop crucial number sense that underpins all future mathematical learning.
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Why it matters
Number representation skills directly impact children's ability to understand place value, perform mental arithmetic, and solve real-world problems. In Reception, pupils who master representing numbers to 20 using concrete materials show 34% better performance in Year 1 addition tasks. These skills appear everywhere: counting pocket money (£2.50 shown as 2 pound coins and 5 ten-pence pieces), tallying football goals scored during break time, or understanding that 'fifteen' biscuits equals 1 ten-frame plus 5 extras. Strong representation skills help children recognise that 23 can be shown as twenty-three, 2 tens and 3 ones, or ||||| ||||| ||||| ||||| ||| tally marks. This flexibility supports mental maths strategies and prepares pupils for more complex concepts like expanded form (400 + 60 + 7 = 467) required in Key Stage 2.
How to solve represent numbers
Representing Numbers
- Numbers can be shown as digits, words, or on a number line.
- Use base-10 blocks: hundreds squares, tens rods, ones cubes.
- Tally marks: groups of 5 (four lines crossed by a fifth).
- Match each representation to the same value.
Example: The number 23: two tens rods + three ones cubes.
Worked examples
How many tally marks? ||||| |
Answer: 6
- Count the tally marks → 6 — Each group of ||||| = 5. Count the groups and add any extras: 6.
What number do these blocks show? [10] [1] [1] [1]
Answer: 13
- Count the ten-blocks → 1 x 10 = 10 — There are 1 blocks of 10.
- Count the one-blocks → 3 x 1 = 3 — There are 3 blocks of 1. Total: 10 + 3 = 13.
What number is made from 90 + 9?
Answer: 99
- Add the values → 90 + 9 = 99 — 90 + 9 = 99.
Common mistakes
- Pupils often miscount tally marks by treating each line as 1 instead of recognising groups of 5, writing ||||| |||| as 9 instead of 14.
- Children frequently confuse tens and ones positions, representing 42 with 4 ones blocks and 2 tens blocks, showing 24 instead.
- Students mix up expanded form addition, writing 60 + 8 = 614 instead of 68 by placing digits side-by-side rather than adding values.