Measuring Mass Units

Overview

Year Group: Primary 5 (Age 9-10)
Duration: 50 minutes
Class Size: 28 students
Unit: Understanding Mass Measurement (Lesson 1 of 3)

---

National Curriculum Links

• Mathematics - Measurement (Year 5)

  • Statutory requirements:
    • Convert between different units of metric measure (e.g., kg and g).
    • Understand and use approximate equivalences between metric units and imperial units (e.g., pounds and kilograms).
    • Solve problems involving measurement and estimation of mass.

• Key Objectives:

  • Recognise and use standard units of mass.
  • Use scales and measuring equipment accurately.
  • Begin to understand and apply conversions between kg, g, and lbs.

---

WALT

We Are Learning To:

• Choose appropriate units for estimating weight.
• Identify and read kg, g, and lbs on scales.

---

Success Criteria

By the end of this lesson, students will be able to:

• Identify the units kg, g, and lbs in written and practical contexts.
• Accurately read masses on different types of scales labelled with these units.
• Demonstrate understanding through estimation and comparison.

---

Resources

• Visual aids: Charts showing units with pictures (kg, g, lbs)
• Realistic scales (digital and analogue) displaying kg, g, and lbs
• Sets of objects of known mass (e.g., fruit, small bags, classroom objects)
• Handouts printed with dyslexia-friendly fonts (OpenDyslexic or similar), clear spacing, and bullet points
• Whiteboard and markers
• Conversion fact cards (for advanced learners)

---

Lesson Structure

1. Introduction (10 minutes)

• Engage: Show students different objects and ask about their weight, e.g., "How heavy do you think this apple is?" Encourage guesses and introduce the idea of mass units.
• Explain: Present a visual aid displaying the units kg, g, and lbs with examples:
  • kg (kilogram): for heavier items (e.g., a bag of sugar)
  • g (gram): for lighter items (e.g., a chocolate bar)
  • lbs (pounds): common imperial unit in UK homes for body weight, etc.
• Write the units clearly on the whiteboard using a dyslexia-friendly font style and spacing.
• Show the conversion approximate: 1 kg ≈ 2.2 lbs (used later for challenge).

---

2. Guided Practice (15 minutes)

• Activity: Group Work (Groups of 4-5)

  • Rotate around stations with scales labelled in kg/g, and lbs.
  • Each group estimates the weight of an object, then reads the actual mass on the scale.
  • Record answers on a worksheet (large font, clear layout) with columns for object, estimated mass, actual mass, unit.

• Teacher support:

  • Circulate, provide visual prompts or reminders of how to identify units.
  • Support students who struggle to read scales or units, using tactile objects or paired reading.

---

3. Differentiated Tasks (15 minutes)

Group	Task Description	Support / Extension
Support Group (lower ability/reading difficulties)	Identify units from flashcards; match units to objects by using pictures and scales with large digits	Use visual aids and peer support; extra time; tactile activities (handling physical scale models)
Main Group (working at expected level)	Complete identification and reading tasks from scales, recording masses and units accurately on worksheets	Teacher guides reading and checks unit understanding
Extension Group (advanced learners)	Convert weights from kg to lbs using simple multiplication (x 2.2) and approximate conversion	Use fact cards; challenge to write conversion explanation or create a mini-poster comparing units

---

4. Plenary (8 minutes)

• Class Discussion:

  • Ask volunteers to share their findings: Which units did they find easiest to use? Which objects were best measured in grams vs kilograms?
  • Introduce the idea that choosing the correct unit makes measuring easier and more accurate.
  • Encourage students to explain back the meaning of kg, g, and lbs in their own words.

• Quick Quiz:

  • Show images of various items and ask students to hold up cards with “kg,” “g,” or “lbs” to indicate what units they should use for estimating mass.

---

5. Assessment and Feedback

• Observe group work to assess correct unit identification and scale reading.
• Review worksheets for accuracy in reading scales and unit labelling.
• Give verbal feedback and praise.
• Provide notes for students with difficulties, and enrichment notes for advanced learners on conversion.

---

Differentiation Strategies

• Visual aids and large clear texts for dyslexic learners with accessible handouts.
• Peer support and paired reading.
• Hands-on activities with real objects and tactile scale use.
• Varied group tasks based on ability.
• Extension tasks to challenge advanced learners with conversions.

---

Dyslexia-Friendly Features

• Use OpenDyslexic or a sans-serif font such as Arial or Comic Sans in all written materials.
• Lines and texts spaced generously (at least 1.5 line spacing).
• Bullet points instead of dense paragraphs.
• High contrast background and text colours (black on white or cream).
• Use symbols alongside words to reinforce meaning (e.g., scales icon next to unit names).

---

Homework Suggestion

• Find 3 household items and estimate their weight using kg or g.
• Ask an adult if they know their weight in lbs or kg and write it down.
• Encourage exploration of measuring mass at home.

---

Reflection for Next Lesson

• Evaluate students’ confidence reading scales and distinguishing units.
• Plan to deepen conversion skills between metric and imperial units.
• Incorporate more problem-solving tasks involving mass estimation and measurement.

---

Summary

This lesson ensures pupils satisfy the Year 5 National Curriculum objectives by recognising and reading units of mass, estimating weights accurately, and using standard measuring scales, while supporting diverse learners and stretching more able students with conversion challenges. The multi-sensory and visual approach caters well to varied learning needs and ensures strong engagement.