How many students are in your school? With Estimate Then Investigate, students will apply estimation strategies and mathematical thinking to predict the total school population before comparing their predictions with actual data. This hands-on activity encourages reasoning, discussion, and use of operations such as doubling, multiplying, and adding to create logical estimates.

Students begin by using a calculation table with known class sizes or rough estimates to work through the problem. They’ll then refine their guesses by comparing to real-world data, strengthening both their number sense and their appreciation for how maths applies to everyday questions. This activity promotes inquiry, cooperation, and analytical thinking.

The resource includes a ready-to-use class list table with common class names, as well as a blank template so you can personalise the activity to suit your school’s structure. It’s ideal for small groups or whole-class modelling, and works well in both lower and upper primary settings.

Key Learning Outcomes:

• ✅ Apply estimation skills to real-life problems
• ✅ Use multiplication, doubling, and addition to make logical predictions
• ✅ Compare estimates with actual figures and reflect on accuracy
• ✅ Develop number sense and confidence with multi-step calculations
• ✅ Collaborate and justify mathematical thinking

What’s Included:

• Pre-filled calculation table with standard class labels
• Blank version for schools with unique class names or structures
• Instructions for facilitating estimation and discussion
• Extension questions and reflection prompts

Materials Needed:

• Printed worksheet templates (A4 or enlarge to A3 for group work)
• Pencils and highlighters
• Optional access to school enrolment records for comparison

How to Use:

1. Discuss what estimation is and why it’s useful in maths and everyday life.
2. Display the pre-filled calculation table and model estimating based on one class's size.
3. Students complete the rest of the table using operations to estimate a total.
4. Reveal the real student numbers from your school and compare.
5. Reflect on differences and discuss what strategies led to the closest estimates.

Ideas for Classroom Use:

• 💡 Use during a maths investigation block as part of a unit on estimation or problem solving.
• 💡 Pair students for collaborative problem-solving and peer discussion.
• 💡 Use as a warm-up before diving into related addition or multiplication lessons.
• 💡 Extend by estimating staff numbers, classrooms, or books in the school library.

Top Teacher Tips:

• 💛 Personalise the blank template with your school’s class names to make the task more relevant.
• 💛 Laminate copies for small group work or use in maths centres with whiteboard markers.
• 💛 Use this task as a launchpad for a larger data collection or graphing activity.

Estimate Then Investigate transforms everyday curiosity into a rich mathematical experience, helping students build confidence and accuracy in their estimation strategies while applying real-world thinking.