Courseversity

Measuring capacity

Primary EducationGrade 3MathematicsCV-PRI-G03-MATH-MEA-U01-L0345–60 min

You will learn

  • Choose ml or litres.
  • Say that 1 L = 1,000 ml.
  • Read a measuring jug.
  • Compare capacities.

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

The lesson in 60 seconds

  1. Use ml for small amounts and L for large.
  2. 1 L = 1,000 ml.
  3. Read the jug at eye level.
  4. Compare in the same unit.

Words to know

capacity
How much a container holds.
millilitre (ml)
A small unit of capacity.
litre (L)
1,000 millilitres.
measuring jug
A jug with a scale.

1. Discover: a water bottle

A bottle holds 1 L of water. You fill cups of 250 ml. How many cups can you fill?

2. Understand: measuring capacity

Capacity is how much a container can hold. We use millilitres (ml) for small amounts (a spoon about 5 ml, a cup about 250 ml) and litres (L) for large amounts (a bucket about 10 L).

1 L = 1,000 ml. So 3 L = 3,000 ml. 3 L 500 ml = 3,500 ml. 1 L holds 4 cups of 250 ml.

Read a measuring jug at eye level, at the bottom of the curved liquid surface.

Idea 1: Units

A teaspoon holds 5 ml. A bucket holds about 10 L. 1 L = 1,000 ml.

Idea 2: Convert

2 L = 2 × 1,000 = 2,000 ml. 1 L 500 ml = 1,500 ml.

Idea 3: Cups

A 2 L jug holds 2,000 ml. 2,000 ÷ 250 = 8 cups.

Why change units? To divide, both amounts must be in the same unit.

Remember: 1 L = 1,000 ml. Use ml for small amounts and L for large.

3. Worked examples

Example 1 (I show you): Convert

2 L in ml?

  1. 2 × 1,000.

Answer: 2,000 ml

Example 2 (We do it together): Combine

1 L 500 ml in ml?

  1. 1,000 + 500.

Answer: 1,500 ml

Example 3 (You try): Cups

How many 250 ml cups fill 2 L?

Show the steps and answer
  1. 2,000 ÷ 250.

Answer: 8

Did you know?

Capacity is how much a container holds.

Why this matters

We measure capacity when we cook, drink and fill tanks.

4. Explore: fill and measure

You need a measuring jug and a cup.

  1. Fill the cup and pour into the jug.
  2. Read the amount in ml.
  3. Count how many cups fill 1 L.
  4. Write 1 L = ___ ml.
Think about it: what did you notice?

4 cups of 250 ml fill 1 L.

5. Practise

Say it in a sentence

Use these starters when you talk about the lesson. Say them out loud.

  • I use ___ because ___.
  • 1 L = ___ ml.
  • ___ ml = ___ L.
  • ___ cups of ___ ml fill ___.

Guided practice

Question 1. 1 L in ml?

1,000 ml.

Question 2. 3 L 500 ml in ml?

3,500 ml.

Question 3. Cups of 250 ml in 1 L?

4.

Independent practice

Level 1: Start

  1. 2 L in ml
  2. 4,000 ml in L
  3. 1 L 500 ml in ml
  4. Unit for a bucket
  5. How many cups of 250 ml in 2 L?

Level 2: Grow

  1. 3 L in ml
  2. 6,000 ml in L
  3. 2 L 100 ml in ml

Level 3: Stretch

  1. 10 cups of 200 ml. How many L?
  2. 4 L 50 ml in ml
  3. Kofi says 1 L = 100 ml. What is wrong?

Answers are in the answer key below. Try first, then check.

6. Apply: everyday mathematics

A jug holds 2 L. How many 250 ml cups can it fill?

Show a sample answer

8 cups.

Another one. A bucket holds 10 L. A mug holds 250 ml. How many mugs fill the bucket?

Show a sample answer

40 mugs

7. Common mistakes

Mistake: Confusing ml and L.
Fix: L is bigger; 1 L = 1,000 ml.
Another mistake: Thinking 1 L = 100 ml.
Fix: 1 L = 1,000 ml.
Another mistake: Comparing ml and L numbers directly.
Fix: Convert to the same unit first.

8. Lesson summary and revision card

I can…

  • I can choose ml or litres.
  • I know 1 L = 1,000 ml.
  • I can read a measuring jug.
  • I can compare capacities.

9. Check and master

Answer all 14 questions. You will see feedback after each one.

1. 1 L =

2. 3 L 500 ml =

3. A cup holds about…

4. Cups of 250 ml in 1 L:

5. A bucket holds about…

6. 5 L in ml =

7. 3,000 ml in L =

8. 2 L 250 ml in ml =

9. A teaspoon holds about…

10. The best unit for a bottle of medicine is…

11. How many 250 ml cups fill 3 L?

12. Which holds more: 1,500 ml or 1 L 200 ml?

Challenge 1. How many 250 ml cups fill a 2 L jug?

Challenge 2. A 5 L tank is 3/5 full. How many ml are in it?

Your result appears here after you answer every question.

10. Key takeaways

  • ml small, L large.
  • 1 L = 1,000 ml.
  • Read the jug at eye level.

11. Next lesson

Next lesson: Standard measurement units. 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.

  1. 2 L in ml? [1 mark]
  2. 4,000 ml in L? [1 mark]
  3. 1 L 500 ml in ml? [2 marks]
  4. How many 250 ml cups fill a 2 L jug? [2 marks]
  5. Ana says 1 L = 100 ml. Is she right? Explain. [3 marks]

Total: 9 marks.

Marking guide and model answers
  1. 2,000 ml [1]
  2. 4 L [1]
  3. 1,000 + 500 [1] = 1,500 ml [1]
  4. 2,000 ÷ 250 [1] = 8 [1]
  5. No [1]. 1 L = 1,000 ml [1]. 100 ml is a tenth of a litre [1].

Score guide: 8 to 9 = secure. 6 to 7 = nearly there, revise the parts you missed. Under 6 = work through the lesson again with a grown-up.

Printable worksheet

  1. 2 L in ml
  2. 4,000 ml in L
  3. 1 L 500 ml in ml
  4. Unit for a bucket
  5. Cups of 250 ml in 2 L
  6. 1 L = ___ ml
  7. 3 L 500 ml = ___ ml
  8. A cup holds about ___ ml.
  9. Cups of 250 ml in 1 L: ___
  10. A bucket holds about ___ L.

Homework

Measure the capacity of three containers at home. Order them.

Answer key and marking scheme

Question Expected response Marks
2 L in ml 2,000 2
4,000 ml in L 4 2
1 L 500 ml in ml 1,500 2
Unit for a bucket L 2
Cups of 250 ml in 2 L 8 2
Total 10

Practice answers: Worksheet: 1 2,000; 2 4; 3 1,500; 4 L; 5 8.

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 1,000; 7 3,500; 8 250; 9 4; 10 10.

Independent practice answers. Level 1: 1 2,000 ml; 2 4 L; 3 1,500 ml; 4 litres (L); 5 8 cups. Level 2: 1 3,000 ml; 2 6 L; 3 2,100 ml. Level 3: 1 2 L; 2 4,050 ml; 3 1 L = 1,000 ml. 100 ml is a tenth of a litre..

Mastery and remediation

Objective Bronze (Developing) Silver (Proficient) Gold (Advanced)
O1 Choose ml or litres 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 Say that 1 L = 1,000 ml 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 Read a measuring jug 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 Compare capacities 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

  1. Find the misconception: Confusing ml and L. L is bigger; 1 L = 1,000 ml.
  2. Explain another way: use real objects first, then pictures.
  3. Show a simpler example: Pour a cup into a litre jug and count.
  4. Guided practice: work through one example together and let the learner try the next one.
  5. Reassess: use the quiz again or the worksheet.
  6. Move on when the learner shows Silver-level evidence independently.

For parents and guardians

In this lesson your child measures and converts capacity. You do not need to be good at mathematics to help.

  • Measure water with a jug and cups.
  • Ask: ml or litres?
  • Check labels on bottles.
  • 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: choose ml or litres; say that 1 L = 1,000 ml; read a measuring jug; compare capacities.

Prerequisite knowledge. Lessons 1 and 2.

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 a measuring jug and a cup. 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. ml or L? Same unit? How many fit?

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. Confusing ml and L. L is bigger; 1 L = 1,000 ml.

13–15. Assessment questions, answer keys, marking scheme

Use the quiz and worksheet on this page. The 9-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. Pour a cup into a litre jug and count. 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 » Measurement & Data. These pages list the standards that cover this topic area; read them alongside the lesson.

Research used to shape this lesson. Common Core 3.MD.A.2 and 4.MD.A.1; Cambridge Primary Mathematics Stage 3 (capacity). These sources informed the lesson.

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