Primary 1 maths · Whole numbers · About 8 minutes
Read and write number names to 100
Say the tens, then the ones.
Start the interactive lesson →Related practice: Firefly forest
What you will learn
- Read and write number names to 100
Models used: number sentences, stories, diagrams.
Before you start
Every digit has a job
The counters are sorted into columns. Each column tells us the size of its units.
The number at the top of each column is the value of one counter in that column.
The counters are sorted into columns. Each column tells us the size of its units.
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.
Look at the left column. Its digit counts the biggest units in this number.
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.
Now read the value of every column. A zero keeps an empty place ready.
32
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.
Put the values together. These are different ways to describe the very same number.
30 + 2
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.
What did the picture help us see?
Put the values together. These are different ways to describe the very same number.
Worked example: A new example, together
Write “thirty” in numerals.
The number at the top of each column is the value of one counter in that column.
Say the tens, then the ones.
Number words and numerals describe the same groups of place-value units.
The number at the top of each column is the value of one counter in that column.
Read the largest place-value group first, then each smaller group.
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.
Write “thirty” in numerals.
30
The number at the top of each column is the value of one counter in that column.
Empty columns still need zeroes in the numeral.
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.
30 is thirty.
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.
Check the result against the question we started with.
Read the result back: thirty = 30.
We found 30. Number words and numerals describe the same groups of place-value units.
Common mistakes to discuss
- Writing what you hear. “Three thousand and five” is 3005, not 30005. Each group of three digits needs its empty places filled with zeros.
Check your understanding
- Read and write number names to 100
- write a number from its name
- 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
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