Negative numbers: what children learn
Negative numbers are numbers less than zero, such as −3 or −10. Year 5 pupils learn to interpret negative numbers in context and count forwards and backwards with positive and negative whole numbers, including through zero. Temperature is the most common context: −4 °C is 4 degrees below freezing.
In this game the number line runs from −10 to 10, with −10, −5, 0, 5 and 10 labelled. Some questions simply ask children to place a number; others give a temperature to mark. Placing negative numbers shows clearly that −7 is further left, and so smaller, than −2.
This topic covers the Year 5 statutory requirement in the National Curriculum in England (Number – number and place value): pupils should be taught to “interpret negative numbers in context, count forwards and backwards with positive and negative whole numbers, including through 0”. Year 5 pupils are usually aged 9–10.
For families following US standards, the closest Common Core standard is 6.NS.C.6.c, which is taught in Grade 6. Common Core introduces negative numbers in Grade 6.
How to play
Move the marker to the right place on the number line, then press Check. You can drag, tap the line or use the arrow keys. Each game has 8 rounds. After you press Check, a green arrow shows the correct position if you were not quite right.
Step by step
- Zero is the middle. Positive numbers are to the right of zero and negative numbers to the left.
- Negative numbers get smaller as you go left. −8 is less than −3, even though 8 is bigger than 3. On a thermometer, −8 °C is colder than −3 °C.
- Count back through zero. Counting back from 3: 2, 1, 0, −1, −2, −3. Don't skip zero.
- Use the nearest label. To place −7, start at −5 and count two steps to the left.
Worked examples
Example 1: Put −7 on the number line.
Working: From −5, count 2 steps left: −6, −7.
Answer: Two ticks to the left of −5
Example 2: The temperature is −2 °C. Mark it.
Working: Two steps to the left of 0.
Answer: Two ticks to the left of 0
Example 3: It is 3 °C and the temperature falls by 5 degrees. What is it now?
Working: Count back 5 from 3: 2, 1, 0, −1, −2.
Answer: −2 °C
Common mistakes and how to fix them
- Thinking −8 is bigger than −3. Use a thermometer: which is colder? Colder means a smaller number.
- Forgetting to count zero when crossing it. Say each number aloud, including zero, while pointing at the ticks.
- Placing negative numbers to the right of zero. Draw an arrow on the line showing which way is 'more' and which way is 'less'.
Activities to try at home
- Check the weather forecast in winter and compare temperatures below zero.
- Use a lift with basement floors: floor −2 is two floors below ground.
- Talk about bank balances or game scores that go below zero.
Ideas for the classroom
- Use a vertical number line like a thermometer and ask 'it rises by 6 degrees from −4; what is the temperature now?'
- Order a set of world city temperatures in January.
- Find the difference between two temperatures across zero, which leads into Year 6 work on intervals across zero.
Printable worksheet
The printable worksheet uses the same question generator as the game, so it practises exactly the same skills. It comes with a separate answer sheet on the second page. Print it, or save it as a PDF from your browser's print menu.
Frequently asked questions
Is −10 smaller than −1?
Yes. −10 is further left on the number line (and colder on a thermometer).
How do you write negative numbers?
With a minus sign in front, such as −5. You can say 'negative five' or 'minus five'.
When do children calculate with negative numbers?
Year 6 pupils calculate intervals across zero, such as the difference between −4 °C and 7 °C. Adding and subtracting negative numbers formally comes at Key Stage 3.
What is the US equivalent?
The Common Core introduces negative numbers in Grade 6 (6.NS.C.5 and 6.NS.C.6.c).