Measuring Mass Today

Overview

Duration: 45 minutes
Class size: 11 students
Unit: Measuring Mass with Cubes (Lesson 2 of 5)
Year group: Year 1
National Curriculum links:

• Mathematics > Measurement > Recognise and use language relating to dates, including days of the week, weeks, months and years (for baseline understanding of measurement concepts).
• Mathematics > Measurement > Compare, describe and solve practical problems for mass/weight (Year 1 Programme of Study - Measurement).
• Statutory requirements:
  • Compare, describe and solve practical problems for mass/weight [for example, heavy/light]
  • Measure and begin to record mass/weight

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Learning Objectives

By the end of this lesson, students will:

• Understand mass as a property that can be measured using non-standard units (cubes).
• Use balance scales to compare the mass of two different objects.
• Record which object is heavier or lighter using cubes as units of mass.
• Begin to develop vocabulary associated with mass (heavy, light, heavier, lighter, equal).

Linked National Curriculum Objective:

"Compare, describe and solve practical problems for mass/weight [for example, heavy/light]" (Key Stage 1, Year 1)

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Key Vocabulary

• Mass
• Cube (non-standard unit)
• Heavy
• Light
• Balance scale
• Heavier than
• Lighter than
• Equal mass

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Resources Needed

• Balance scales (one per pair of students or small group)
• Cubes (uniform 1 cm³ connecting cubes) around 50 per group
• Assortment of classroom objects with varied mass (e.g., pencil, eraser, small book, toy car)
• Worksheets: Record sheet with pictures of objects and spaces to note cubes counted
• Large visual vocabulary chart with key words and images
• Whiteboard and markers
• Timer or stopwatch
• Sticky notes for quick assessment at end

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Lesson Structure

1. Starter (5 minutes): Interactive Mass Talk

• Gather students in a circle with two contrasting objects (e.g., a toy car and a feather).
• Ask: "Which do you think is heavier? Which is lighter? Why?" Prompt discussion with hands-on handling of objects.
• Introduce the balance scale and briefly demonstrate how it works to compare the two objects without cubes.
• Emphasise the key vocabulary: heavier, lighter, balance scale.

2. Introduction to Measuring Mass with Cubes (10 minutes)

• Demonstrate placing an object on one side of the balance scale.
• Show how to add cubes one by one to the other side until the scale balances.
• Explain: "When the scale balances, the number of cubes is the same as the mass of the object."
• Write on the board: "Mass of [object] = ___ cubes" as an example.
• Reinforce the concept that cubes are non-standard units but help us compare and measure mass.

3. Guided Activity: Comparing Masses Using Balance Scales (15 minutes)

• Divide students into pairs or small groups (2-3 pupils) to explore balance scales and cubes.
• Each group receives two classroom objects of different masses and cubes.
• Steps:
  1. Place the first object on the left side of the scale.
  2. Add cubes on the right side until balanced. Count cubes aloud.
  3. Record number of cubes to represent the object's mass on their worksheet.
  4. Repeat for the second object.
  5. Compare number of cubes and discuss which object is heavier, lighter, or if equal.
• Teacher circulates and supports, asking guided questions: "How many cubes does this object need? Which object is heavier based on cubes?"

4. Class Discussion and Concept Consolidation (10 minutes)

• Regroup students on the carpet or at tables.
• Invite a few pairs to share their results with the class, showing objects and cube measurements.
• Use a large visual balance scale on the board or interactive whiteboard to demonstrate balancing cubes and objects.
• Elicit and reinforce vocabulary: "This object has 7 cubes, this one has 4 cubes. Which is heavier? Which is lighter? Can they be equal?"
• Highlight that more cubes = more mass.

5. Plenary and Assessment (5 minutes)

• Use quick-fire oral questions: Show two objects or pictures, ask "Which is heavier?" or "How many cubes to balance?"
• Distribute sticky notes for "One thing I learned today..." — Students write or draw (with adult help) one thing about measuring mass using cubes.
• Collect sticky notes for a quick formative assessment of understanding.

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Differentiation

• Support: Provide one-to-one help with counting cubes; use simplified objects.
• Challenge: Encourage students to order three objects by mass using cubes; introduce simple addition by combining cubes.

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Assessment Opportunities

• Observation during paired activities of correct use of balance scales and cube counting.
• Worksheet completion accuracy for cube measurement recordings.
• Sticky note reflections to check conceptual understanding and vocabulary use.

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Reflection Notes for Teachers

• Encourage students to verbalise reasoning to deepen conceptual understanding.
• Offer plenty of hands-on practice; young learners benefit from tactile and visual learning.
• Use everyday classroom objects to make mass meaningful.
• Linking this lesson to daily activities (e.g., weighing ingredients, comparing objects at home) supports knowledge retention.

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By structuring the lesson around rich, hands-on activities with clear measurement concepts rooted firmly in the Year 1 National Curriculum, this session should engage students deeply while developing foundational measurement skills critical for later maths learning.