Shape Investigators Aotearoa

Overview

In this first lesson of Year 4 Maths Across Aotearoa, learners investigate familiar 2D shapes and 3D objects by handling, naming, describing and sorting them. The lesson establishes geometry vocabulary and mathematical discussion routines through an I do, We do, You do sequence, followed by a tactile Shape Detective investigation.

Learning intentions

• WALT recognise and name common 2D shapes and 3D objects.
• WALT describe faces, edges, vertices and curved surfaces.
• WALT sort shapes and objects using a clear mathematical rule.
• WALT explain our thinking using words, drawings or models.

Success criteria

• I can name and sort at least four shapes or objects.
• I can describe two properties of a prism.
• I can explain why a cylinder is not a prism.
• I can use the words face, edge, vertex and curved surface correctly.

Curriculum links

• Geometry: recognising, describing and sorting 2D shapes and 3D objects.
• Mathematical reasoning: identifying properties, noticing similarities and differences, and justifying a classification.
• Mathematical communication: using precise vocabulary, models, drawings and oral explanations.
• Mathsteasers: developing higher-order thinking through challenge, explanation and multiple ways of seeing a problem.

Lesson structure (60 minutes)

1. 0–7 min · Hook and notice. Open the Shape Investigators opening slides and show a mystery bag or covered collection containing a cube, sphere, cylinder and triangular prism. Ask, “What clues could help us identify an object without knowing its name?” Students silently observe, then share one noticing and one wondering with a partner. Record useful vocabulary without correcting every idea immediately.

2. 7–17 min · I do: model vocabulary. Use concrete models and the vocabulary and worked-example slides to model a cube and sphere. Point to and count the parts: a cube has 6 square faces, 12 edges and 8 vertices; a sphere has one curved surface and no edges or vertices. Explicitly distinguish a flat face from a curved surface and explain that a vertex is a corner where edges meet. Students copy a quick labelled sketch or rehearse the words with actions.

3. 17–27 min · We do: classify together. Display a cube, cuboid, triangular prism, pyramid, cylinder, cone and sphere. Sort the objects first by a teacher-selected rule, such as “has a curved surface/does not have a curved surface”, then invite learners to suggest another rule. Use the sorting discussion slides to prompt: “Which objects belong together?”, “What is your rule?”, and “Does every object fit?” Students discuss in pairs, justify one placement, and help build a class sorting chart.

4. 27–45 min · You do: Shape Detective investigation. Place groups of five around tables with a mixed collection of concrete shapes and objects. Distribute the Shape Detective recording sheet. Students choose or are assigned four objects, name each, draw or photograph it if available, record relevant faces, edges, vertices and curved surfaces, and sort the collection using their own rule. Encourage groups to handle each object and check counts rather than guessing. Circulate and ask, “How do you know?”, “What evidence supports your rule?”, and “Could this object fit somewhere else?”

5. 45–54 min · Challenge and share. Return to the prism challenge and share slides. Groups share one classification and one surprising result. Set the three differentiated prompts: Must Do: name and sort four shapes; Can Do: describe two prism properties; Try: explain why a cylinder is not a prism. Accept explanations such as “A prism has flat polygon faces and matching parallel ends; a cylinder has a curved surface and circular ends, so it is not a prism.” Students compare explanations and improve one answer using precise vocabulary.

6. 54–60 min · Plenary and assessment. Use the final reflection slides to revisit the learning intention. Students complete the final section of the Shape Detective recording sheet: draw or describe one object, label one property, and answer, “How is a sphere different from a cube?” Invite two or three oral responses, then collect sheets for checking.

Resources

• the Shape Investigators slide deck
• the Shape Detective recording sheet
• Concrete 2D shape tiles and 3D geometric objects
• Mystery bag or cloth
• Sorting hoops, trays or large paper circles
• Whiteboard and markers
• Pencils, crayons and optional tablets or cameras
• Word bank cards: face, edge, vertex, curved surface, prism, pyramid, cylinder, sphere

Assessment

• Listen for correct use of face, edge, vertex and curved surface during modelling, partner talk and group investigation.
• Check whether learners can name four objects, sort them according to a stated rule, and record observable properties rather than guesses.
• Use the final comparison and prism/cylinder explanations to identify learners needing further teaching about flat and curved surfaces or prism properties.

Differentiation

• Provide real objects, photographs, labelled examples, a word bank and sentence starters such as “I sorted these together because…” and “I know this is a prism because…”.
• Offer oral, drawn, photographed or scribed responses, and allow extra processing time before requiring an explanation.
• Support learners who need it by limiting the initial collection to four familiar objects and counting properties together; pair learners strategically and use tactile exploration before written recording.
• Extend confident learners by asking them to create two different sorting rules, compare a cube and cuboid, or defend whether a triangular prism belongs with a pyramid.