Mathematics · Year 2

Active learning ideas

Standard Units of Capacity

Active learning works for standard units of capacity because young learners need to physically experience volume to build lasting understanding. Pouring, comparing, and building with litres and millilitres helps students move from guessing to measuring with confidence.

• National Curriculum Attainment Targets
• KS1: Mathematics - Measurement

• 25–40 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Stations Rotation
• 30 min · Pairs

Pairs: Estimate and Measure

Pairs select classroom containers, estimate capacity in ml or l, then use measuring jugs to check and record actual amounts. They calculate estimation errors and share one insight with the class. Adjust water levels to compare similar-sized but different-capacity items.

Explain the difference between a liter and a milliliter.

Facilitation Tip

During Pairs: Estimate and Measure, remind students to check their partner’s reading before recording to reduce measurement errors.

What to look for

Give students two containers, one holding 500ml of water and another holding 1 liter. Ask them to write down which container holds more and explain why, using the terms liter and milliliter.

• Remember
• Understand
• Apply
• Analyze
• Self-Management
• Relationship Skills

Activity 02

• Stations Rotation
• 40 min · Small Groups

Small Groups: Build 1 Litre

Groups gather small containers and pour water to total exactly 1 litre, recording each contribution in ml. They combine totals and verify with a 1-litre jug. Discuss why some plans used more containers than others.

Justify why we use different units for measuring small and large amounts of liquid.

Facilitation Tip

When students Build 1 Litre, circulate with a 1-litre jug to verify each group’s container as they progress.

What to look for

Present students with a list of items (e.g., a swimming pool, a teaspoon of cough syrup, a bottle of juice, a bathtub). Ask them to write 'l' next to items typically measured in liters and 'ml' next to items typically measured in milliliters.

• Remember
• Understand
• Apply
• Analyze
• Self-Management
• Relationship Skills

Activity 03

• Stations Rotation
• 35 min · Whole Class

Whole Class: Capacity Sort

Display various containers; class estimates and measures each using shared jugs, then sorts them from smallest to largest capacity on a line. Record units used and vote on trickiest estimates. Review as a group.

Construct a plan to measure the capacity of various containers.

Facilitation Tip

For Capacity Sort, provide at least two containers of the same capacity but different shapes to challenge visual assumptions directly.

What to look for

Pose the question: 'Imagine you are helping a chef prepare a large batch of soup and a single serving of sauce. Which unit of measurement, liters or milliliters, would be best for each task, and why?'

• Remember
• Understand
• Apply
• Analyze
• Self-Management
• Relationship Skills

Activity 04

• Stations Rotation
• 25 min · Individual

Individual: Measurement Plan

Each student plans steps to measure a familiar item's capacity, like a school milk carton, choosing units and tools. They test plans solo, record results, and note adjustments needed.

Explain the difference between a liter and a milliliter.

Facilitation Tip

In Measurement Plan, model how to write unit choices with numbers, like ‘500 ml’ or ‘2 l’, to reinforce precise recording.

What to look for

Give students two containers, one holding 500ml of water and another holding 1 liter. Ask them to write down which container holds more and explain why, using the terms liter and milliliter.

• Remember
• Understand
• Apply
• Analyze
• Self-Management
• Relationship Skills

A few notes on teaching this unit

Teach this topic by balancing exploration with structure. Start with concrete pouring tasks to build schema, then move to abstract comparisons. Avoid rushing to abstract symbols before students have felt the difference between 100 ml and 1 litre. Research shows that repeated, varied practice with real containers strengthens spatial reasoning about volume, so plan for multiple short sessions rather than one long lesson.

By the end of these activities, students will confidently estimate volumes, select the right unit, and measure accurately using litres and millilitres. They will justify their choices and correct common misconceptions through hands-on evidence.

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Watch Out for These Misconceptions

• During Pairs: Estimate and Measure, watch for students who record 100 ml as the same size as 1 litre because they see the same number.

  Ask pairs to pour ten 100 ml measures into a litre jug while counting aloud, then compare the total volume to a full 1-litre container to see the 1000 ml total together.

• During Capacity Sort, expect students to assume taller containers always hold more liquid.

  Provide a tall thin and a short wide container with the same capacity, have students fill both, then pour between them to observe equal volumes despite different heights.

• During Measurement Plan, listen for students who insist litres are used for every liquid measurement task.

  Have students sort real-life items into two trays labelled ‘ml’ and ‘l’, then justify their choices in a group discussion, using the items to show why scale matters.

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Methods used in this brief

• Stations Rotation