Mathematics · Year 2

Active learning ideas

Comparing and Estimating Capacity

Active, hands-on tasks let students feel volume and see relationships between containers, turning abstract comparisons into concrete understanding. Moving, pouring, and ordering containers builds spatial reasoning and measurement skills that paper-based exercises cannot match.

• National Curriculum Attainment Targets
• KS1: Mathematics - Measurement

• 25–50 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Experiential Learning
• 30 min · Pairs

Pair Prediction Challenge: Shape Surprises

Pairs choose two different-shaped containers and predict which holds more without pouring, using visual cues like width. They test by filling both with water using a standard cup, then compare levels. Record results on a simple chart and switch pairs to try new containers.

Predict which container holds more liquid without pouring.

Facilitation Tip

During Pair Prediction Challenge, give each pair two very different-shaped containers and a small scoop for immediate testing so they see the link between prediction and measurement right away.

What to look for

Provide students with two different-sized cups and a small scoop. Ask them to predict which cup holds more scoops of water and then test their prediction. On the ticket, they write: 'I predict ____ holds more. I tested it by using ____ scoops. My prediction was ____.'

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 02

• Experiential Learning
• 45 min · Small Groups

Small Group Relay: Capacity Ordering

Provide five containers of varying capacities. Groups estimate the order from least to most using handfuls of beans as units, then verify by pouring water through a funnel. Discuss why estimates were close or off, and reorder accurately.

Compare the capacity of different-shaped containers.

Facilitation Tip

In Small Group Relay, assign each group a ‘capacity ruler’ made of 10 identical spoons so teams can count scoops and compare results aloud.

What to look for

Hold up three containers of varying capacities. Ask students to point to the container they think holds the least, then the most. Follow up by asking one student to explain their choice for the 'most' container, using a phrase like 'because it looks wider' or 'it's taller'.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 03

• Experiential Learning
• 50 min · Whole Class

Whole Class Experiment: Bottle Capacity Test

Display two bottles; class votes on which holds more and suggests test methods. Select and perform the experiment together, filling simultaneously with coloured water. Chart class predictions versus actual results for group reflection.

Design an experiment to find out which of two bottles holds more water.

Facilitation Tip

For Whole Class Experiment, line up six marked bottles with increasing capacities and have students fill them side by side to create a visible, ordered scale they can refer to later.

What to look for

Present students with a tall, thin container and a short, wide container that hold the same amount of water. Ask: 'If I fill this tall cup with water, and then pour it into this short, wide cup, will it be more, less, or the same amount? Why do you think so?' Listen for explanations related to volume and shape.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 04

• Experiential Learning
• 25 min · Individual

Individual Estimation Hunt: Classroom Containers

Each child selects three classroom items like mugs or vases, estimates capacity in cupfuls, then measures to check. Share one accurate estimate with the class and explain reasoning.

Predict which container holds more liquid without pouring.

What to look for

Provide students with two different-sized cups and a small scoop. Ask them to predict which cup holds more scoops of water and then test their prediction. On the ticket, they write: 'I predict ____ holds more. I tested it by using ____ scoops. My prediction was ____.'

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

A few notes on teaching this unit

Start with a quick demonstration of pouring between two containers to show that volume stays constant even when shape changes. Avoid lecture on formulas; let repeated measuring and discussion reveal patterns. Use phrases like ‘Show me how you know’ to prompt reasoning. Research suggests that children build lasting understanding through cycles of prediction, test, and reflection rather than single explanations.

Children will confidently predict and test which container holds more liquid, explain their reasoning using shape and size, and use non-standard units to measure capacity accurately. They will recognize that height alone does not determine capacity and will revise predictions based on evidence.

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Watch Out for These Misconceptions

• During Pair Prediction Challenge, watch for students who assume the taller container holds more without considering width.

  Hand each pair a short wide cup and a tall narrow cup, give them a scoop, and ask them to pour and count together, then ask which shape ‘won’ and why.

• During Small Group Relay, watch for students who treat estimates as random guesses without using units.

  Have each group use the same spoon-sized scoop and record the count on a mini whiteboard, then share totals aloud so peers challenge vague claims like ‘a lot’ with precise numbers.

• During Whole Class Experiment, watch for students who think capacity depends only on visible size.

  Show a tall thin and short wide bottle of equal capacity, fill one, pour into the other, and ask the class to compare heights and still conclude the amounts are the same, using the evidence from the pour.

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Methods used in this brief

• Experiential Learning