Measuring Capacity Together

Overview

In this 60-minute practical investigation, learners compare capacity and volume, measure in millilitres and litres, and describe volume using cubic units. They build on prior work with measurement, multiplication and arrays by connecting repeated measures with efficient calculation.

Learning intentions

• WALT compare the capacity of different containers.
• WALT measure and record capacity using millilitres and litres.
• WALT find the volume of rectangular blocks by counting cubic units or using multiplication.
• WALT explain our mathematical thinking using accurate measurement language.

Success criteria

• I can explain the difference between capacity and volume.
• I can convert 2 L to 2,000 mL.
• I can find the volume of a block such as 3 × 2 × 2 as 12 cubic units.
• I can make a prediction, test it fairly and explain my conclusion.

Curriculum links

• Mathematics and Statistics — Mathsteasers: higher-order thinking questions that challenge learners and deepen understanding.
• Mathematics and Statistics — Mathsteasers / Alignment: mathematical challenge connected to classroom content.
• Mathematics and Statistics — Mathsteasers / Additional resources for advanced learners: reasoning, investigation and problem solving.

Lesson structure (60 minutes)

1. 0–5 min · Hook and prediction. Display three differently shaped containers and ask, “Which one holds the most? How could we prove it?” Open with the hook and prediction slides. Students silently choose a container, share a reason with a partner and record a prediction on the capacity and volume investigation sheet.

2. 5–15 min · Connect capacity and volume. Use the teaching slides to clarify that capacity is how much a container can hold, while volume is the amount of space an object occupies. Teacher fills a 1 L container using ten 100 mL measures, recording 100 mL, 200 mL and so on; students count along, identify the pattern and state that 1 L = 1,000 mL. Students then use the Units Conversion Ladder as a visual reference to complete the Must Do: 2 L = 2,000 mL.

3. 15–23 min · Model cubic volume. Build a 3 × 2 × 2 rectangular block with cubes. Teacher demonstrates counting three layers of four cubes, then records 3 × 2 × 2 = 12 cubic units. Show a 4 × 2 × 2 block and invite students to predict before confirming that its volume is 16 cubic units. Students sketch one block and explain whether they counted cubes, layers or used multiplication.

4. 23–43 min · Container Investigation. Arrange 25 learners in five groups of five, with each group investigating two or three containers. Explain safe routines: water stays on trays, dry materials are poured slowly, and spills are wiped immediately. Students predict which container has greater capacity, measure using 100 mL cups or another agreed unit, record results in a table and compare the evidence with their prediction. Open the investigation instruction and recording slides and refer students to the investigation table and questions.

5. 43–52 min · Compare and reason. Groups display or read one result. Teacher prompts: “Did the taller container always hold more?”, “Was the amount measured exactly?”, and “How did you make the comparison fair?” Students use sentence stems such as “Our evidence shows…” and “We know because…”. Invite groups to compare one container’s capacity in millilitres with a 1 L container.

6. 52–60 min · Plenary and exit check. Revisit the prediction question using the discussion and plenary slides. Students complete the final questions on the exit check: convert 2 L to millilitres, find the volume of a 4 × 2 × 2 block, and write one difference between capacity and volume. Collect sheets as learners leave.

Resources

• the capacity and volume slide deck
• the capacity and volume investigation sheet
• the Units Conversion Ladder
• One 1 L container and a range of smaller measuring containers
• 100 mL measuring cups or jugs
• Water and/or dry materials such as rice, sand or pasta
• Linking cubes or unit cubes
• Trays, towels and aprons
• Pencils, clipboards and group recording tools

Assessment

• Listen for correct use of capacity, volume, millilitres, litres and cubic units during modelling and group talk.
• Check predictions, measurement tables and explanations for fair comparisons and appropriate units.
• Use the exit check to identify learners who can convert units and calculate volume, then group learners for follow-up practice.

Differentiation

• Provide visual scales, the conversion ladder, partially completed tables and sentence starters such as “The capacity is ___ mL because…”.
• Offer no-touch roles, including prediction recorder, equipment manager, photographer, observer and oral reporter. Learners may use photos, drawings or oral recordings instead of writing every result.
• For learners needing support, use only 100 mL measures first and build a 1 L container together before comparing other capacities.
• Extend confident learners by asking them to find two different rectangular blocks with a volume of 24 cubic units, or to explain why container shape does not always show capacity.