# Lesson 86: Place value — tens and ones

🧮 MATH (40 Lessons) • 🟢 A. Numbers and Counting

← Back to Level 1

## Objective

I can show a 2-digit number using tens and ones. I can say how many tens and how many ones are in a number like 23.

## Materials

- Small sticks, straws, or craft sticks (to make bundles of ten)
- Small objects for ones (cubes, counters, or buttons)
- Paper or a notebook and a pencil

## Mini-lesson — Tens and ones in 2-digit numbers

A 2-digit number (like 23) is made from tens and ones.

Tens

- Ten ones can be grouped into one ten.
- We can show one ten with a bundle of 10 sticks or a long rod.
- Two tens means 20, three tens means 30, and so on.

Ones

- Ones are the single pieces that are not in a bundle of ten.
- If you have 3 loose cubes, that is 3 ones.
- Ones change the last digit of the number (for example, the 3 in 23).

Reading a number like 23

- In 23, the 2 means 2 tens (20).
- The 3 means 3 ones.
- So 23 is 2 tens and 3 ones.

You will build numbers with tens (bundles) and ones (single pieces), then read them out loud.

Picture strip: Tens rods and ones cubes.

20 = 2 tens, 0 ones

23 = 2 tens, 3 ones

## Guided Practice — Build numbers with tens and ones

You will use real objects to build numbers with tens and ones. Then you will trace important place value words.

1. Make tens: Count 10 sticks and tie them or line them up as one bundle. This is 1 ten.
2. Make ones: Keep some small objects as single ones.
3. Build a number: Choose a 2-digit number between 11 and 39 (for example, 24). Build it using bundles of ten and single ones.
4. Say the tens and ones: For your number, say out loud:
   "24 is 2 tens and 4 ones."
5. Write on paper: On your paper, write your number and a matching sentence. Example:
   24 = 2 tens and 4 ones.
6. Use the tracing pad: Choose two words that match your work (for example, tens and ones) and trace them on the pad.
7. Add a small picture: Next to the word tens, draw a tiny rod. Next to the word ones, draw a tiny cube.

Tracing Pad
Lines
Trace
Pen

## Practice 1 — Tens and ones with models

[PLACEHOLDER PRACTICE 1]

## Practice 2 — Match numbers to tens and ones

[PLACEHOLDER PRACTICE 2]

## Practice 3 — Place value stories

[PLACEHOLDER PRACTICE 3]

## Quick Check — Place value: tens and ones

Answer each question about tens, ones, and 2-digit numbers. You may look back at the mini-lesson.

1) In the number 23, what does the 2 mean?

2 ones 2 tens 20 ones and 3 tens
In 23, the 2 is in the tens place, so it means 2 tens.

2) In the number 23, what does the 3 mean?

3 tens 30 ones 3 ones
The last digit shows the ones. 3 means 3 ones.

3) How many tens are in 40?

4 tens 40 tens 1 ten
40 is 4 groups of ten, so 4 tens.

4) How many ones are in 40?

4 ones 0 ones 10 ones
The ones digit is 0, so there are 0 ones.

5) Which number has 2 tens and 5 ones?

15 52 25
2 tens and 5 ones makes 25.

6) Which number has 3 tens and 1 one?

31 13 30
3 tens and 1 one is 31 (not 13).

7) A model shows 1 ten and 7 ones. Which number is it?

70 17 71
1 ten (10) and 7 ones makes 17.

8) A model shows 2 tens and 0 ones. Which number is it?

2 12 20
2 tens is 20. Zero ones does not change the number.

9) Which part of a 2-digit number shows the tens?

The first digit (on the left) The second digit (on the right) Both digits are ones
In a 2-digit number, the left digit shows the tens place.

10) Which part shows the ones?

The first digit (on the left) The second digit (on the right) There are no ones
The last digit is the ones place.

11) Which number shows the same tens but more ones than 42?

40 32 47
47 has 4 tens like 42, but 7 ones, which is more than 2 ones.

12) Which picture matches 34?

3 tens rods and 4 small cubes 4 tens rods and 3 small cubes 3 small cubes and 4 tens rods
34 is 3 tens and 4 ones.

13) A model shows 4 tens and 2 ones. How do we say it?

four tens and twenty ones four tens and two ones forty-two tens
We say it as four tens and two ones (42).

14) Why is place value important?

It helps us know what each digit means It only helps us tell time It is only for zero
Place value tells us what each digit stands for in a number.

15) Which sentence is true?

In 25, the 5 is the tens digit In 25, the 2 is the ones digit In 25, the 2 is the tens digit and the 5 is the ones digit
25 has 2 tens (20) and 5 ones.

## Assessment (parent/teacher)

Student can show a 2-digit number using tens and ones. Student can say how many tens are in a number like 34. Student can say how many ones are in a number like 34. Student can match place value models to written numbers. Student uses the words tens and ones correctly when talking about numbers.

## Exit ticket (student)

😀 I can read tens and ones easily. 🙂 I understand tens and ones but need more practice. 😅 Tens and ones still feel tricky for me.

#### Next time I will practise…

Building numbers with tens and ones Reading the tens and ones in a 2-digit number Matching models to numbers like 23 or 34
← Lesson 85 Lesson 87 →