Capacity for children

Quick answer

Capacity is how much liquid or material a container can hold. You can measure it using cups, jugs, litres, and millilitres.

Learning outcome

By the end of this page, you will understand how to compare and measure the capacity of different containers using everyday tools and units like millilitres and litres.

• You can tell which container holds more or less liquid.
• You can use a measuring jug to find out how much a container holds.
• You can compare containers using words like full, half full, empty, and nearly full.
• You can use litres and millilitres to measure capacity.

Why this matters

Capacity helps us understand how much things can hold. This is useful when cooking, filling up a water bottle, or deciding how much juice to pour. It’s also important for science, building, and even playing games!

Knowing about capacity helps you make smart choices, like not overfilling a cup or making sure you have enough water for a hike.

How it works

Capacity is measured using units like millilitres (ml) and litres (l). A millilitre is a very small amount, like a few drops of water. A litre is much bigger – about the size of a small milk carton.

Here’s how you can measure capacity:

1. Look at two containers and guess which one holds more.
2. Fill one container with water or sand.
3. Pour the liquid or material into a measuring jug or container with markings.
4. Read the number on the jug to see how much it holds.
5. Compare your results with the other container.

Examples you can see

Let’s imagine you have a cup and a jar. You pour water into the cup and find it holds 250 ml. Then you pour water into the jar and find it holds 500 ml. So the jar holds more than the cup.

Another example: a bucket can hold 10 litres of water, while a teacup holds only 250 ml. That means the bucket holds 40 times more water than the teacup!

Try this: Use a small cup to fill a big jug. Count how many small cups it takes to fill the jug. That shows how much the jug holds in terms of small cups.

Try it as a mini adventure

Adventure: The Water Challenge

You are on a camping trip and need to fill up your water bottles. You have a small bottle that holds 300 ml, a medium bottle that holds 500 ml, and a large bottle that holds 1 litre.

Your challenge: Fill each bottle with water and compare how much each one holds. Then, use a measuring jug to check if your guesses were right.

Step 1: Guess which bottle holds the most water.

Step 2: Fill each bottle with water.

Step 3: Pour the water from each bottle into a measuring jug.

Step 4: Record how much each bottle holds.

Step 5: Compare your results to your guess.

Common mistakes

• Mistake: Thinking that a tall container holds more than a short one.
• Why it happens: The shape can trick your eyes.
• Fix: Pour the liquid from one container into another to compare directly.

• Mistake: Confusing millilitres and litres.
• Why it happens: Both are measurements of capacity, and they sound similar.
• Fix: Remember that 1 litre = 1000 millilitres. Use a litre jug to see the difference.

• Mistake: Not reading the measuring scale correctly.
• Why it happens: The markings can be tricky to read.
• Fix: Look at the bottom of the liquid level, not the top. Use a ruler or a stick to help you read.

Parent and carer guide

Help your child understand capacity by doing fun activities at home. Here’s how in 5–10 minutes:

1. Set up a container challenge: Use different cups, jugs, and bottles. Ask your child to guess which holds more.
2. Use measuring tools: Let them pour water from one container to another and see what happens.
3. Compare real-life examples: Ask how much milk is in a carton, or how many cups of water are in a jug.
4. Encourage thinking: Ask questions like, “Why do you think this container holds more?” or “What do you notice about the shape?”
5. Be patient: It’s normal for children to mix up capacity at first. Keep practicing!

Remember: Capacity is about how much a container can hold, not how full it is. So even if a container is only half full, it still holds the same amount.

Practice questions

1. Which holds more: a 250 ml cup or a 500 ml bottle?
2. A jug holds 1 litre. How many millilitres is that?
3. If a bucket holds 3 litres and a bottle holds 500 ml, how many bottles can fill the bucket?
4. Which is bigger: 1000 ml or 1 litre?
5. Fill in the blank: 2 litres = ______ ml

Answers:

1. The 500 ml bottle holds more.
2. 1000 ml
3. 6 bottles (since 3 litres = 3000 ml, and 3000 ÷ 500 = 6)
4. They are the same (1000 ml = 1 litre)
5. 2000 ml

FAQ

What is capacity?

Capacity is how much a container can hold. It’s measured in units like millilitres (ml) and litres (l).

How do I measure capacity?

You can use a measuring jug or a container with markings to see how much liquid or material a container holds.

What’s the difference between millilitres and litres?

A millilitre is a small amount, like a few drops. A litre is much bigger, about the size of a small milk carton.

Why is capacity important?

Capacity helps us know how much water, juice, or sand a container can hold. It’s useful in cooking, science, and daily life.

Can I use any container to measure capacity?

Yes! You can use any container with clear sides and markings. If it doesn’t have markings, you can use a measuring jug to check how much it holds.