Looking for a fun and interactive way to explore measurement in your early years or Year 1-2 classroom? Mass Mix Up is a hands-on sorting activity designed to help students practise distinguishing between the units of grams and kilograms. With colourful images and simple instructions, this resource provides the perfect opportunity for students to consolidate their understanding of mass in a meaningful and engaging context.

By sorting object cards into the appropriate category, students will build fluency in estimating the mass of everyday items and choosing the correct unit of measurement. The use of real-world visuals makes the concept of mass more accessible and relatable to young learners, and the interactive nature of the task supports kinaesthetic learning. It’s an ideal way to reinforce key measurement vocabulary and promote classroom discussions around when and why we use different units of measure.

This resource offers great flexibility in its delivery. Whether you use it as part of a whole-class introduction, small group rotation or independent practice task, Mass Mix Up can be easily adapted to suit the needs of your students. The simple format also makes it a perfect option for early finishers or a quick review session at the end of a lesson.

Key Learning Outcomes:

• ✅ Identify the difference between grams and kilograms
• ✅ Estimate the mass of everyday objects
• ✅ Sort items according to appropriate units of mass
• ✅ Use measurement language such as “light”, “heavy”, “grams” and “kilograms”

What’s Included:

• Printable object image cards featuring everyday classroom and household items
• Two sorting mats labelled “grams” and “kilograms”
• Teacher instruction sheet with tips for effective use

Materials Needed:

• Printed and cut image cards
• Sorting mats for small groups or individuals
• Laminator (optional for reusability)
• Envelopes or zip lock bags to store each set

How to Use:

1. Introduce or revise the concept of grams and kilograms with your class.
2. Show students how to estimate mass using familiar objects as benchmarks.
3. Provide each group or student with a set of image cards and two sorting mats.
4. Students take turns picking up a card, estimating its mass and placing it under “grams” or “kilograms”.
5. Discuss as a class or in pairs why certain objects belong in each category.

Ideas for Classroom Use:

• 💡 Use in maths rotations with mixed ability groups
• 💡 Send a simplified version home as a family learning task
• 💡 Encourage students to bring in items from home to expand the card set

Top Teacher Tips:

• 💛 Laminate the cards and sorting mats for repeated use
• 💛 Allow time for students to explain their thinking as they sort
• 💛 Add a third category like “not sure” to prompt deeper discussion or peer support

Mass Mix Up is a fantastic way to support early understanding of measurement in your classroom. With vibrant visuals, real-world connections and collaborative opportunities, it’s a must-have for your next mass unit.