Mass Mystery Task Cards are a fun and hands-on way to explore mass using informal units. Perfect for Foundation and Year 1 learners, these engaging cards provide open-ended measurement challenges that encourage critical thinking and experimentation with weight.

Students will use balance scales and easily accessible classroom objects to complete each measuring task. The cards prompt students to make predictions, test using informal units, and record their results. For an extra challenge, one set of task cards includes marbles as the informal unit, encouraging consistency and discussion around standardisation.

This resource is ideal for whole-class instruction, maths groups, or as a fast finisher activity. With a variety of tasks and minimal prep required, these cards are perfect for reinforcing key measurement concepts in a playful and purposeful way.

Key Learning Outcomes:

• ✅ Compare the mass of everyday objects using informal units
• ✅ Use balance scales to conduct hands-on investigations
• ✅ Record and reflect on findings using visual representations
• ✅ Develop prediction and comparison skills using mass vocabulary

What’s Included:

• Set of Mass Mystery Task Cards using general classroom objects
• Additional set using marbles as a standard informal unit
• Optional student recording sheet
• Teacher instructions and suggestions for classroom use

Materials Needed:

• Printed task cards and recording sheets
• Balance scales or equal-arm scales
• Marbles (or counters) as informal units
• A variety of classroom objects (e.g. erasers, glue sticks, blocks, scissors)
• Pencils or crayons for recording

How to Use:

1. Distribute task cards to individual students, pairs or small groups
2. Students read the challenge and make a prediction based on weight
3. Using a balance scale, they test objects and determine results
4. Record findings using the optional recording sheet
5. Repeat the process with new task cards to explore more objects

Ideas for Classroom Use:

• 💡 Use as part of a whole-class introduction to comparing mass
• 💡 Rotate through small group maths centres for measurement focus
• 💡 Provide as a fast finisher activity with minimal supervision
• 💡 Extend learning by having students design their own mystery mass challenges

Top Teacher Tips:

• 💛 Laminate the cards for reuse year after year
• 💛 Encourage students to explain their thinking using full sentences (e.g. “The scissors are heavier than the pencil because the scale tipped.”)
• 💛 Use a mix of predictable and surprising object pairings to keep students engaged

Looking for more mass fun? Pair this activity with the following:

• Marbles for MASS
• Measure it Up
• Measuring MASS Worksheet

Mass Mystery Task Cards offer an engaging way to investigate mass through prediction, comparison and hands-on experimentation. Get ready to explore, test and measure with this versatile classroom favourite!