Mathematics Subject Enrichment Activity

Class 4

Topic

Rounding Off Numbers to the Nearest 10, 100, and 1000

Activity Title

🎴 Round and Round

Aim

To understand and apply the concept of rounding numbers.
To round numbers to the nearest 10, 100, and 1000.
To improve number sense and estimation skills.
To develop strategic thinking through a card game.
To strengthen mental mathematics skills.

Learning Outcomes

Students will be able to:

✔ Round 2-digit numbers to the nearest 10.

✔ Round 3-digit numbers to the nearest 100.

✔ Round 4-digit numbers to the nearest 1000.

✔ Compare numbers and estimate values quickly.

✔ Use mathematical reasoning while playing games.

Materials Required

A deck of playing cards
Paper
Pencil
Highlighters or coloured pencils
Scale (optional)

Preparation

Remove all:
- 10s
- Jacks
- Queens
- Kings
Let:
- Ace = 1
Count the remaining cards.

Total cards = 36

Shuffle the cards well.

Procedure

Round 1 – Nearest 10

Step 1

Deal all cards equally between two players.

Step 2

Write the following score sheet:

10, 20, 30, 40, 50, 60, 70, 80, 90, 100

Step 3

Each player uses two cards to form a 2-digit number.

Step 4

Round the number to the nearest 10.

Step 5

Highlight the corresponding number on the score sheet.

Step 6

A highlighted number cannot be used again.

Step 7

Continue until all numbers are covered.

Step 8

Count highlighted numbers to determine the winner.

Round 2 – Challenge Round

Step 1

Deal only 10 cards to each player.

Step 2

Follow the same rules as Round 1.

Step 3

If a player cannot form a new rounded number, the other player continues scoring.

Round 3 – Nearest 100

Step 1

Deal all cards equally.

Step 2

Write the score sheet:

100, 200, 300, 400, 500, 600, 700, 800, 900, 1000

Step 3

Use three cards to form a 3-digit number.

Step 4

Round to the nearest 100.

Step 5

Highlight the matching score.

Round 4 – Nearest 1000

Step 1

Deal all cards equally.

Step 2

Write the score sheet:

1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000

Step 3

Use four cards to form a 4-digit number.

Step 4

Round to the nearest 1000.

Step 5

Highlight the rounded value.

Step 6

Continue until all cards are used.

Observation Table

Round 1 (Nearest 10)

Number Formed	Rounded Number
34	30
68	70
75	80
92	90
57	60

Round 3 (Nearest 100)

Number Formed	Rounded Number
243	200
367	400
589	600
821	800
950	1000

Round 4 (Nearest 1000)

Number Formed	Rounded Number
1245	1000
2698	3000
5432	5000
6789	7000
9501	10000

Solutions

Example 1

Number = 47

Ones digit = 7

7 ≥ 5

Round up

47 ≈ 50

Example 2

Number = 382

Tens digit = 8

8 ≥ 5

Round up

382 ≈ 400

Example 3

Number = 6487

Hundreds digit = 4

4 < 5

Round down

6487 ≈ 6000

Rules for Rounding

Nearest 10

Ones digit 0–4 → Round Down
Ones digit 5–9 → Round Up

Nearest 100

Tens digit 0–4 → Round Down
Tens digit 5–9 → Round Up

Nearest 1000

Hundreds digit 0–4 → Round Down
Hundreds digit 5–9 → Round Up

Observations

Numbers ending in 5 or more round up.
Numbers ending in less than 5 round down.
Rounding helps estimate numbers quickly.
Larger place values require looking at the digit immediately to the right.
The game improves both accuracy and speed.

Reflection

I learned how to round numbers to different place values.
I enjoyed learning mathematics through a game.
I can estimate numbers more confidently now.
I understood why rounding is useful in daily life.
Working with cards made learning fun and interactive.

HOTS (Higher Order Thinking Skills)

Q1. Using the cards 2, 4, and 8, form the largest 3-digit number. Round it to the nearest 100.

Answer

Largest number = 842

842 ≈ 800

Q2. Using the cards 1, 5, 7, and 9, form the smallest 4-digit number. Round it to the nearest 1000.

Answer

Smallest number = 1579

1579 ≈ 2000

Q3. Can two different numbers round to the same hundred?

Answer

Yes.

Example:

241 ≈ 200

249 ≈ 200

Both round to 200.

Q4. Find three numbers that round to 500.

Answer

451 ≈ 500

498 ≈ 500

549 ≈ 500

Q5. Why is rounding useful in real life?

Answer

Rounding helps us:

Estimate shopping bills.
Approximate distances.
Calculate quickly.
Check whether answers are reasonable.
Make mental calculations easier.

Conclusion

The Round and Round activity helped students understand the concept of rounding numbers through a fun card game. It strengthened estimation skills, number sense, and mental mathematics while encouraging logical thinking, teamwork, and strategic decision-making. 🎴🔢✨