Building 3D Models

Overview

Lesson 11 of 15 in Shapes, Space and Reasoning. In a group of five, learners construct cubes, prisms and composite objects from 2D nets or everyday materials, then describe their models using the language of faces, edges and vertices.

Learning intentions

• WALT construct 3D models from 2D faces or everyday materials.
• WALT identify and describe faces, edges and vertices.
• WALT explain how the parts of a model connect to form a solid.
• WALT communicate mathematical thinking using drawings, gestures, speech, writing or signs.

Success criteria

• I can construct a cube, prism or composite 3D model.
• I can identify and count its faces, edges and vertices.
• I can describe the shape and properties of my model accurately.
• I can explain one choice I made while building.

Curriculum links

• Geometry: recognise, describe, classify and construct two- and three-dimensional shapes.
• Spatial reasoning: visualise how 2D faces and nets form 3D objects.
• Mathematical communication: use diagrams, objects and appropriate geometric language to explain ideas.
• Key competencies: thinking; using language, symbols and texts; managing self; relating to others.

Lesson structure (60 minutes)

1. 0–7 minutes – Engage and connect

Display a photograph or model of a package, building or toy made from simple solids. Open with the introduction and visual hook slides and ask: “What 2D shapes can you see on the outside? How might these faces join to make a solid?” Accept spoken, signed, drawn or pointed responses. Introduce the learning intention and success criteria.

2. 7–15 minutes – Teacher modelling

Use a large net or connected blocks to model folding and joining a cube and a triangular or rectangular prism. Demonstrate from the front, side and above, pausing so all learners can see clearly. Use the signed and visual vocabulary for face, edge, vertex/vertices, net, cube, prism and composite. Refer to the modelling and vocabulary slides. Explicitly show that an edge is where two faces meet and a vertex is a corner where edges meet.

3. 15–20 minutes – Plan the build

Give each learner a choice of a ready-made net, linking cubes, construction connectors, boxes or other safe everyday materials. Hand out the 3D Shape Nets Pack for learners choosing a net. Briefly discuss which faces will meet and where the tabs or connectors will be used. Learners sketch or select a model plan on the 3D model planning and recording worksheet.

4. 20–40 minutes – Build and investigate

Learners work individually or in pairs, with the teacher supporting one learner at a time. They build a cube, prism or composite object, checking whether it stands, closes and matches their plan. Encourage learners to rotate the object and view it from several angles. Use the build instructions and checking prompts to remind learners to ask: “Are all faces connected? Which faces are congruent? How many edges and vertices can I find?”

5. 40–50 minutes – Describe and improve

Each learner completes the recording section of the 3D model planning and recording worksheet by drawing the model and recording its type, faces, edges and vertices. Partners use a visual pointing or signing routine to give feedback: “I notice…”, “I counted…”, and “Check…”. Learners improve their model or correct their count if needed.

6. 50–57 minutes – Share and reason

Invite each learner to show the model from at least two viewpoints and explain one design choice. Use the sharing and reasoning prompts. Compare models: Which have flat faces? Which have the same number of faces? How does a composite object differ from a single prism? Record useful observations where everyone can see them.

7. 57–60 minutes – Plenary and check

Return to the success criteria using the plenary slide. Each learner points to or signs one face, one edge and one vertex on their model, then gives a final verbal, written, drawn or signed response: “My model is a ___ because ___.” Collect the worksheets and photograph models if they will be used in the next lesson.

Resources

• the complete 3D modelling slide deck
• the 3D model planning and recording worksheet
• the 3D Shape Nets Pack
• Cardboard boxes, cereal cartons or other clean everyday packaging
• Linking cubes, building blocks or construction connectors
• Scissors, glue or masking tape
• Large demonstration net or pre-built models
• Whiteboard and markers
• Visual or signed vocabulary cards, if available
• Five trays or workspaces for organising materials

Assessment

• Observe whether each learner selects, joins and stabilises appropriate faces or materials to construct a recognisable 3D model.
• Listen to, watch or read each learner’s description of faces, edges and vertices; accept accurate signs, gestures, diagrams and written labels.
• Use the worksheet and final response to identify who can count and justify properties independently, and who needs further work with visualising nets or distinguishing edges from vertices.

Differentiation

• Provide ready-made nets, pre-folded starting points, step-by-step visual instructions and a completed example. Pair learners strategically for peer support.
• Offer larger cardboard faces, chunky blocks, wide tape and adapted scissors for learners needing improved motor or visual access.
• For Deaf learners, give practical visual instruction, model from multiple viewpoints, keep hands and face visible, and explicitly teach signed vocabulary alongside printed labels. Check understanding through demonstration rather than relying only on spoken explanation.
• Support EAL learners with labelled diagrams, gestures, sentence frames such as “My model has ___ faces,” and opportunities to rehearse with a partner. Reduce the number of shapes or counting demands where appropriate.

Extension

Challenge advanced learners to build a composite object that has at least two different types of prisms, or meets given constraints such as “exactly 10 faces” or “more edges than vertices”. They must record the properties, explain how they know their counts are correct, and justify why their chosen faces fit together.