Mathematics · 3rd Year

Active learning ideas

Measuring Mass (kg, g)

Measuring mass is a practical skill that becomes much clearer when students can interact with objects and tools directly. Experiential learning and station rotations allow students to build an intuitive understanding of grams and kilograms through hands-on practice, moving beyond abstract definitions.

• NCCA Curriculum Specifications
• NCCA: Primary - Measurement

• 20–45 min
• Pairs → Whole Class
• 3 activities

Activity 01

• Stations Rotation
• 45 min · Small Groups

Stations Rotation: Mass Measurement Challenge

Set up stations with different objects (e.g., fruits, books, small toys) and scales. Students rotate in small groups, measuring the mass of each object in both grams and kilograms, recording their findings, and discussing which unit is more appropriate for each item.

Explain how to decide whether to use grams or kilograms for an object.

Facilitation Tip

During the Stations Rotation, ensure each station has a clear set of instructions and a variety of objects with noticeably different masses to emphasize unit choice.

• Remember
• Understand
• Apply
• Analyze
• Self-Management
• Relationship Skills

Activity 02

• Experiential Learning
• 30 min · Pairs

Design a Mass Comparison Experiment

In pairs, students select two objects and design a simple experiment to compare their masses using scales. They must outline their procedure, conduct the measurement, and present their findings, justifying why one object has more or less mass than the other.

Design an experiment to compare the mass of two different objects.

Facilitation Tip

For the Design a Mass Comparison Experiment, prompt pairs to consider what makes their chosen objects good candidates for comparison and how they will present their findings.

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

Activity 03

• Experiential Learning
• 20 min · Individual

Zeroing In: Scale Accuracy Check

Whole class discussion on the importance of zeroing scales. Students then individually or in pairs test various scales, deliberately not zeroing them, measuring an object, and then zeroing and remeasuring to observe the difference in results.

Analyze the importance of zeroing a scale before measuring.

Facilitation Tip

During Zeroing In: Scale Accuracy Check, encourage students to articulate why a scale must be zeroed before use, connecting it to the accuracy of their measurements.

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

A few notes on teaching this unit

This topic benefits from a teaching approach that prioritizes hands-on exploration and concrete examples over purely theoretical explanations. Teachers should model accurate scale usage, including zeroing and unit selection, before students engage in independent practice. Emphasize the 'why' behind each step, connecting measurements to real-world scenarios.

Students will be able to accurately measure the mass of various objects using scales, differentiating between the appropriate use of grams and kilograms. They will demonstrate an understanding of the importance of scale calibration and the relationship between the two units.

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Watch Out for These Misconceptions

• During the Mass Measurement Challenge station rotation, watch for students who consistently use only one unit (e.g., always grams) regardless of the object's size.

  Redirect students by asking them to consider the object at their station: 'Would it make sense to describe the mass of this textbook in grams? Why or why not?' Encourage them to record the mass in both units if appropriate to highlight the difference.

• During Zeroing In: Scale Accuracy Check, students might record a measurement without noticing if the scale wasn't zeroed, leading to incorrect conclusions.

  Have students deliberately measure an object twice: once with the scale zeroed and once without, then compare the results. Ask them to explain why the second measurement is inaccurate and how to correct it.

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Methods used in this brief

• Stations Rotation
• Experiential Learning