You will learn
- Find the nearest hundreds for a number.
- Use the tens digit to decide.
- Round numbers up to 10,000 to the nearest hundred.
- Estimate using rounded numbers.
Version 0.2 · expanded edition · built from cited public sources Content is based on the official frameworks and sources listed under Sources and standards. No official endorsement is claimed. Written in the style of common primary school assessments. No exam result is promised.
Student lesson
- Look at the tens digit.
- 5 or more, round up.
- 4 or less, round down.
- Rounded numbers help us estimate.
Words to know
The closest multiple of 100.
Go to the next hundred.
Stay on the lower hundred.
A close answer.
1. Discover: about how many people?
A crowd of 2,468 people is called “about 2,500”. How did the speaker choose 2,500?
2. Understand: rounding to the nearest hundred
To round to the nearest hundred, look at the tens digit. 5 or more: round up. 4 or less: round down.
340 → 300. 350 → 400. 2,468 → 2,500 (tens digit 6). 8,950 → 9,000. 6,049 → 6,000.
Rounded numbers make quick estimates: 2,468 + 3,214 is about 2,500 + 3,200 = 5,700.
Idea 1: The rule
To round to the nearest hundred, look at the tens digit. If it is 5 or more, round up. If it is 4 or less, round down.
Idea 2: Examples
520 rounds to 500. 780 rounds to 800. 3,449 rounds to 3,400.
Idea 3: Carry over
8,950 rounds to 9,000. 6,049 rounds to 6,000.
Why the tens digit? It shows whether we are past the halfway point.
3. Worked examples
Example 1 (I show you): Down
Round 520 to the nearest hundred.
- Tens digit 2 is less than 5.
Answer: 500
Example 2 (We do it together): Up
Round 780 to the nearest hundred.
- Tens digit 8 is 5 or more.
Answer: 800
Example 3 (You try): Carry
Round 8,950 to the nearest hundred.
Show the steps and answer
- Tens digit 5 rounds up. 89 hundreds + 1 = 90.
Answer: 9,000
Did you know?
The halfway point between 500 and 600 is 550.
Why this matters
Rounding makes mental estimates fast.
4. Explore: round and estimate
You need paper and a pencil.
- Round 340, 350 and 2,468.
- Round 8,950 and 6,049.
- Estimate 2,468 + 3,214.
- Check that the estimate is close.
Think about it: what did you notice?
300, 400, 2,500; 9,000, 6,000; about 5,700.
5. Practise
Say it in a sentence
Use these starters when you talk about the lesson. Say them out loud.
- The tens digit is ___.
- So I round ___.
- The nearest hundred is ___.
- My estimate is ___.
Guided practice
Question 1. Round 340.
300.
Question 2. Round 350.
400.
Question 3. Round 2,468.
2,500.
Independent practice
Level 1: Start
- Round 520
- Round 780
- Round 3,449
- Round 8,950
- Round 6,049
Level 2: Grow
- Round 630
- Round 275
- Round 4,512
Level 3: Stretch
- Round 7,891
- Round 9,960
- Ama rounds 3,449 to 3,500 because 9 is big. What is wrong?
Answers are in the answer key below. Try first, then check.
6. Apply: everyday mathematics
A farmer has 2,468 sacks. Round to the nearest hundred.
Show a sample answer
2,500 sacks.
Another one. A stadium holds 4,670 people. Round to the nearest hundred and explain.
Show a sample answer
4,700, because the tens digit 7 is 5 or more
7. Common mistakes
Fix: Use the tens digit for hundreds.
Fix: Look at the tens digit.
Fix: Only change it if the hundreds carry.
8. Lesson summary and revision card
- I can find the nearest hundred.
- I can use the tens digit.
- I can round up to 10,000.
- I can estimate with rounded numbers.
9. Check and master
Answer all 14 questions. You will see feedback after each one.
Your result appears here after you answer every question.
10. Key takeaways
- Look at the tens digit.
- 5 or more rounds up.
- Estimate with rounded numbers.
11. Next lesson
Next lesson: Number patterns. Keep going with the next idea in this course.
Exam practice
These questions are written in the style of common school and international primary assessments. Try them on your own, without looking back. Then check your answers in the marking guide. The marks are shown in brackets.
- Round 520 to the nearest hundred. [1 mark]
- Round 3,449 to the nearest hundred. [1 mark]
- Round 6,049 to the nearest hundred. [1 mark]
- Estimate 2,468 + 3,214 by rounding to the nearest hundred. [2 marks]
- Kofi says 350 rounds to 300. Is he right? Explain. [3 marks]
Total: 8 marks.
Marking guide and model answers
- 500 [1]
- 3,400 [1]
- 6,000 [1]
- 2,500 + 3,200 [1] = 5,700 [1]
- No [1]. 5 rounds up [1]. It is 400 [1].
Score guide: 7 to 8 = secure. 5 to 6 = nearly there, revise the parts you missed. Under 5 = work through the lesson again with a grown-up.
Printable worksheet
- Round 520
- Round 780
- Round 3,449
- Round 8,950
- Round 6,049
- Round 340
- Round 350
- Round 2,468
- Round 8,950
- Round 6,049
Homework
Round five car prices or distances to the nearest hundred.
Answer key and marking scheme
| Question | Expected response | Marks |
|---|---|---|
| Round 520 | 500 | 2 |
| Round 780 | 800 | 2 |
| Round 3,449 | 3,400 | 2 |
| Round 8,950 | 9,000 | 2 |
| Round 6,049 | 6,000 | 2 |
| Total | 10 |
Practice answers: Worksheet: 1 500; 2 800; 3 3,400; 4 9,000; 5 6,000.
Quiz answers: 1 A, 2 B, 3 C, 4 A, 5 B, 6 A, 7 B, 8 C, 9 A, 10 B, 11 C, 12 A, Challenge 1 C, Challenge 2 C.
Extra worksheet answers (items 6 onward): 6 300; 7 400; 8 2,500; 9 9,000; 10 6,000.
Independent practice answers. Level 1: 1 500; 2 800; 3 3,400; 4 9,000; 5 6,000. Level 2: 1 600; 2 300; 3 4,500. Level 3: 1 7,900; 2 10,000; 3 Look only at the tens digit, 4. Round down to 3,400..
Mastery and remediation
| Objective | Bronze (Developing) | Silver (Proficient) | Gold (Advanced) |
|---|---|---|---|
| O1 Find the nearest hundreds for a number | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O2 Use the tens digit to decide | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O3 Round numbers up to 10,000 to the nearest hundred | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O4 Estimate using rounded numbers | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
Courseversity badge thresholds (overall quiz score): Gold = 90–100%; Silver = 80–89.9%; Bronze = 70–79.9%. A badge is never a full record of progress.
If a learner struggles
- Find the misconception: Using the ones digit to decide. Use the tens digit for hundreds.
- Explain another way: use real objects first, then pictures.
- Show a simpler example: Use a number line from 300 to 400.
- Guided practice: work through one example together and let the learner try the next one.
- Reassess: use the quiz again or the worksheet.
- Move on when the learner shows Silver-level evidence independently.
For parents and guardians
In this lesson your child rounds numbers to the nearest hundred and estimates. You do not need to be good at mathematics to help.
- Round shop prices to the nearest hundred.
- Ask: what is the tens digit?
- Estimate bills together.
- Ask “how do you know?” after each answer, and listen.
- Praise effort, not only right answers. Mistakes are how we learn.
- Ten to fifteen minutes a day is better than one long session.
Teacher package
1–5. Objectives, prerequisites, materials, preparation, duration
Lesson objectives. Learners will: find the nearest hundreds for a number; use the tens digit to decide; round numbers up to 10,000 to the nearest hundred; estimate using rounded numbers.
Prerequisite knowledge. Lesson 6.
Materials. Counters (stones, seeds or bottle tops), paper, pencils, board or chalkboard. Low-resource options: use stones, seeds, sticks, bottle tops or drawings in the sand or on the board instead of printed materials.
Preparation. Gather the counters and draw the example pictures on the board before the lesson.
Suggested duration. 45–60 minutes. It can be split into two shorter sessions.
6–9. Teaching procedure, explanation notes, guided and independent activities
Introduction (5 min). Start with the Discover situation and let learners suggest ideas before you teach.
Explanation (10 min). Teach the Understand section with real objects first, then pictures, then symbols and words.
Guided activity (10 min). You need paper and a pencil. Learners follow the Explore steps in pairs.
Independent activity (10 min). Learners complete the independent practice and the worksheet.
Assessment and reflection (5 min). Ask each learner to say one thing they learned and how they know it.
Key questions. What is the tens digit? Do I round up or down? What is the estimate?
Teacher explanation notes. Use the concrete, pictorial, abstract order: real objects first, then pictures, then symbols and words. Return to real objects whenever a learner needs support.
10–12. Differentiation, formative assessment, common misconceptions
Support. Use real objects and work with a partner; say each step aloud together. Extension. Ask learners to make up their own example and explain it to a partner.
Formative assessment. Listen to learner explanations, ask “how do you know?”, and check the independent work.
Misconceptions. Using the ones digit to decide. Use the tens digit for hundreds.
13–15. Assessment questions, answer keys, marking scheme
Use the quiz and worksheet on this page. The 8-mark exam practice scheme, the 10-mark scheme and all answers are in the answer sections above. Re-check every answer and the marking scheme before publication.
16–19. Remediation, enrichment, homework, teacher reflection
Remediation. Use a number line from 300 to 400. Enrichment. Invite learners to find or create three more examples at home or in the classroom and explain them. Homework. See above.
Teacher reflection. After teaching, record: which concepts learners understood; which misconceptions occurred; which activities worked; which learners need more practice; and what to improve next time.
Sources and standards
This lesson is based on the sources below, and no official endorsement is claimed. Reference starting points named in the Courseversity standard: Common Core State Standards for Mathematics, Cambridge Primary and the IB Primary Years Programme. Where a standard code is named, it points to the official framework.
Official standards for this topic area. Common Core State Standards for Mathematics (official site): Grade 3 » Number & Operations in Base Ten. These pages list the standards that cover this topic area; read them alongside the lesson.
Research used to shape this lesson. Common Core 3.NBT.A.1; Cambridge Primary Mathematics Stage 3 (rounding and estimating). These sources informed the lesson.