Primary 1 maths · Whole numbers · About 8 minutes
Compare and order numbers to 100
Line up matching places. Start on the left.
Start the interactive lesson →Practise: Number crocodile
What you will learn
- Compare and order numbers to 100
Models used: number sentences, stories, diagrams.
Before you start
Look at the biggest groups first
Compare 32 and 28. Each long row represents a group of ten.
The number at the top of each column is the value of one counter in that column.
Compare 32 and 28. Each long row represents a group of ten.
A digit tells us how many units there are. Its position tells us what size those units are; that is why a zero can matter.
The number at the top of each column is the value of one counter in that column.
32 has three tens. 28 has only two tens. Those tens decide the comparison.
A digit tells us how many units there are. Its position tells us what size those units are; that is why a zero can matter.
Both bars use the same scale. Compare their lengths and read the names beside them.
Even though 8 is more than 2, 28 is less than 32. Compare the tens before the ones.
28 < 32
What did the picture help us see?
Even though 8 is more than 2, 28 is less than 32. Compare the tens before the ones.
Worked example: A new example, together
Put 94, 32, 91 in increasing order.
Line up matching places. Start on the left.
Increasing order lists each value from smallest to greatest.
943291Put these number cards in order, smallest first. Compare the greatest place first.
943291Put these number cards in order, smallest first. Put 94, 32, 91 in increasing order.
32, 91, 94
Continue through smaller places when digits match.
943291Put these number cards in order, smallest first. Smallest to greatest: 32, 91, 94.
943291Put these number cards in order, smallest first. Check the result against the question we started with.
Each next number is at least as large as the previous number.
We found 32, 91, 94. Increasing order lists each value from smallest to greatest.
943291Put these number cards in order, smallest first.
Common mistakes to discuss
- Longer looks larger. Compare the greatest place first, not the number of digits on the page. 0 thousands beats nothing: 998 is less than 1002 because the thousands differ.
Check your understanding
- Compare and order numbers to 100
- compare numbers using their places
- check the answer against the original quantities and units
Explain your reasoning to an adult, then try a fresh question in the interactive lesson. A result from one attempt is not proof of lasting mastery.
Try this lesson →Related Primary 1 lessons
- Count and represent numbers to 100Count and represent numbers to 100 · About 8 minutes
- Use tens and onesUse tens and ones · About 8 minutes
- Read and write number names to 100Read and write number names to 100 · About 8 minutes
- Continue number patternsContinue number patterns · About 8 minutes
- Use ordinal numbers from first to tenthUse ordinal numbers from first to tenth · About 8 minutes