# 3D Shapes

3D shapes teaches students how to describe the unique properties of solids using the correct terminology and how to draw them using isometric and elevation drawings.  Students progress onto constructing nets of a range of solids.  This is a key topic before moving onto finding the volume and surface area of cubes and prisms in Year 10 Term 4 for the Higher GCSE  course or Year 11 Term 2 for Foundation.

##### Revision Lessons

Prerequisite Knowledge

• draw 2-D shapes and make 3-D shapes using modelling materials; recognise 3-D shapes in different orientations and describe them
• recognise angles as a property of shape or a description of a turn
• compare and classify geometric shapes, including quadrilaterals and triangles, based on their properties and sizes
• identify acute and obtuse angles and compare and order angles up to two right angles by size
• identify lines of symmetry in 2-D shapes presented in different orientations

Success Criteria

• use conventional terms and notations: points, lines, vertices, edges, planes, parallel lines, perpendicular lines, right angles, polygons, regular polygons and polygons with reflection and/or
• rotation symmetries; use the standard conventions for labelling and referring to the sides and angles of triangles; draw diagrams from written description
• identify properties of the faces, surfaces, edges and vertices of: cubes, cuboids, prisms, cylinders, pyramids, cones and spheres
• construct and interpret plans and elevations of 3D shapes.

Key Concepts

• Understanding and applying the keywords is essential throughout this topic.
• Students need to understand the geometrical difference between a prism and pyramid.
• Horizontal lines are not drawn on isometric paper.

Common Misconceptions

• Students often get confused which elevation to draw and how to include hidden detail.
• Some students find it very difficult to draw 3D shapes on isometric paper.

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