Measuring in Pairs

Overview

In this lesson, students practise measuring mass and capacity using scales and measuring jugs in a hands-on, pair-based way. They record results, check for sensible measurements, and discuss accuracy and precision using “measurement detective” investigations.

Learning intentions

• Students will measure and record mass using a variety of classroom objects and food items.
• Students will measure and record capacity using measuring jugs and containers.
• Students will use correct measuring technique and compare results with peers.
• Students will explain why some measurements are more accurate or more precise.

Success criteria

• I can measure mass in grams using scales correctly and record a number with the unit.
• I can measure capacity in millilitres using a measuring jug correctly and record a number with the unit.
• I can show careful technique (flat placement, level reading, starting/zeroing as needed).
• I can explain how I know my measurement is accurate and how repeated measures help.

Curriculum links

• Use measurement tools to measure and describe mass and capacity, choosing appropriate units.
• Read measurement marks accurately and record measurements using correct units.
• Compare measurements and discuss measurement variation, including accuracy and precision.
• Communicate and justify mathematical thinking using observations and recorded data.

Lesson structure (45 minutes)

1. 0–5 min | Warm-up: “Guess and Check” Display two items (e.g., a small container and a toy) and ask students to predict which is heavier. Share that today they will measure to find out, using correct tool technique.

2. 5–10 min | Mini demonstration: how to measure Model mass measurement: place object in the centre, wait for the reading to settle, and record in grams. Model capacity measurement: pour slowly into a jug, read at eye level from the meniscus (top of the liquid curve), and record in millilitres.

3. 10–12 min | Pair setup and roles Students work in pairs. Assign roles: Measurer and Recorder (switch once during the lesson). Show how to use the data collection sheet: item name, tool used, measurement, and one repeat measurement if required.

4. 12–26 min | Station 1 + Station 2: Measure mass and capacity Students rotate through two guided activity zones (teacher floats; peers help).

• Mass zone: measure 2–3 items (e.g., fruit/packet, small block, cup of dry materials if safe and appropriate).
• Capacity zone: measure 2–3 liquids/containers (e.g., water in small bottles, coloured water for visibility). Students record each measurement with the correct unit and check that readings are reasonable.

5. 26–32 min | Measurement detectives: mystery object challenge Present a “mystery” container or item. Students test hypotheses by measuring (or comparing) against a target range given by the teacher (e.g., “between 50 g and 70 g” or “about 150 mL”). They must record at least one measurement and include a short justification sentence.

6. 32–39 min | Accuracy and precision talk Bring pairs together. Ask: “Who got the same result on a repeat measurement? What changed? How could we measure more precisely?” Focus on technique (steady placement, eye level, slower pouring, avoiding spills) and discuss why repeated measures can reduce uncertainty.

7. 39–45 min | Exit ticket + wrap Students complete a quick exit ticket: one mass measurement and one capacity measurement (from a teacher-prepared sample). They answer one question: “What did you do to make your measurement more accurate?”

Resources

• Digital or dial scales (enough for rotations), with accessible “zero” function if available
• Measuring jugs with visible graduations (e.g., 10 mL and 50 mL increments)
• Classroom objects for mass (blocks, small tools, containers)
• Food items for mass (sealed and safe; teacher-selected)
• Liquids for capacity (water and optionally food dye for visibility) and small funnels/spouts for careful pouring
• Data collection sheets (columns for item, tool, measurement, unit, repeat, notes)
• Clipboards, pencils, erasers, wipes/paper towels
• Measuring “mystery” objects/containers and pre-set target ranges
• Timer for station rotation and a class list of pair roles

Assessment

• Use a practical observation checklist/rubric during pair work: correct tool use, reading accuracy, recording accuracy, and safe handling.
• Review data collection sheets for correct units and sensible measurement values (including repeats where required).
• Check exit ticket responses for understanding of accuracy/precision and correct reading technique.

Differentiation

• Support: Provide sentence starters for recording and discussion (e.g., “I was accurate because…”, “I got a different result when…”). Use fewer items per station and a smaller target range for mystery challenges.
• Support: Assign measuring helpers (teacher or a buddy) to pairs who need extra modelling of how to read scales/jugs at eye level.
• Extension: Ask students to repeat a measurement twice and compare results, then state which method gave the most consistent (precise) results and why.
• EAL/SEN: Offer visual cues on the data sheet (images of scales/jugs, unit labels “g” and “mL”). Allow verbal recording with teacher transcription if handwriting is a barrier, while still capturing the measurement and unit.