Support your students in exploring the fascinating relationship between 3D objects and their cross-sections with our interactive Cross-section 3D Object Nets: Prisms activity! This hands-on resource allows learners to investigate the geometric features of prisms and understand how slicing and construction reveal hidden faces and cross-sections within solid shapes.

By constructing prism nets and physically manipulating them, students will deepen their spatial reasoning and develop a stronger understanding of 2D and 3D geometry. As they fold, cut, and position their models, they will explore how different cross-sections are formed and how these cross-sections connect to the structure of the original solid. This activity also provides an excellent opportunity for students to practise visualisation, reasoning, and mathematical communication skills.

Cross-section 3D Object Nets: Prisms is perfect for whole-class geometry investigations, small group modelling activities, or as a hands-on task for students ready to extend their understanding of 3D shapes. Whether used to introduce cross-sections for the first time or to enrich more advanced exploration of solids, this resource provides an engaging and practical way to bring geometry to life in your classroom.

Key Learning Outcomes:

• ✅ Identify and describe cross-sections of 3D objects
• ✅ Construct prisms using 3D object nets
• ✅ Explore how the direction of a cut affects the resulting cross-section
• ✅ Strengthen visualisation and spatial reasoning skills
• ✅ Develop mathematical language and communication when describing geometric features

What’s Included:

• 3D object nets for:
  • Rectangular prism
  • Triangular prism
  • Pentagonal prism
• Guided instructions for assembling nets and creating interactive cross-sections
• Flexible design to support exploration of multiple cross-sections

Materials Needed:

• Printed Cross-section 3D Object Nets: Prisms (preferably on thick cardstock)
• Scissors
• Glue stick or adhesive
• Sticky tape (for folding edge of cross-section)
• Optional: coloured cardstock for visual impact

How to Use:

1. Print your chosen prism nets on thick cardstock (A4 or enlarged to A3 for ease of assembly).
2. Have students carefully cut out each net and pre-fold the tabs to support clean construction.
3. Students glue and assemble the two prism nets, ensuring neat and accurate folds.
4. Position the two shapes so their cross-section faces are touching, and tape one edge to allow the cross-section to fold open and closed.
5. Encourage students to observe and describe the cross-section and how it connects to the overall geometry of the shape.

Ideas for Classroom Use:

• 💡 Use during whole-class geometry lessons to model how 2D shapes relate to 3D solids.
• 💡 Include as part of a hands-on maths rotation exploring cross-sections and spatial reasoning.
• 💡 Provide for fast finishers or extension groups as a rich open-ended geometry challenge.
• 💡 Use in STEM projects exploring engineering, packaging design, or real-world 3D objects.
• 💡 Encourage students to present and explain their models to classmates to build mathematical communication skills.

Top Teacher Tips:

• 💛 Print on coloured cardstock to make the cross-sections stand out clearly during modelling and discussion.
• 💛 Enlarge nets to A3 for younger students or for collaborative group work.
• 💛 Pre-fold all tabs with students before gluing to ensure neat and accurate construction.
• 💛 Prompt students to sketch and label their cross-sections as a follow-up reflection task.

Cross-section 3D Object Nets: Prisms provides a rich, visual, and interactive way for students to explore the fascinating relationship between 2D and 3D shapes. A fantastic resource for bringing geometry to life and deepening spatial reasoning skills in your classroom!