Year 5, Unit 1, Week 3, Lesson 2
Identifying properties of 3-D shapes
National Curriculum attainment target
Lesson objective
• Identify 3-D shapes, including cubes and other cuboids, from 2-D
representations
• Use properties to identify 3-D shapes from 2-D
representations
Previous related lesson
Future related lessons
Unit 1, Week 3, Lesson 1
Unit 1, Week 3, Lesson 3; Unit 1, Week 3, Lesson 4
Prerequisites for learning
Success criteria
Pupils need to:
Pupils can:
• identify some of the properties of 3-D shapes
• identify properties such as the number of faces, edges and
vertices in 3-D shapes from 2-D representations
Vocabulary
face, edge, vertex, vertices, prism, pyramid, octahedron
Getting Started
• Choose an activity from Geometry – Properties of shapes.
Teach
Resources
Year 5, Unit 1,
Week 3
2 interlocking squares and 12 interlocking equilateral triangles (per class)
1
• Display: Slide 1 showing the seven 3-D shapes.
• Ask: Who can come to the screen and point to the 3-D shapes that have triangular faces?
• Point to each of these shapes in turn and ask: Can you name this shape? (tetrahedron, squarebased pyramid triangular prism)
• Ask: Who can recall the word which means 'a solid shape with many faces'? (polyhedron)
• Ask: How many vertices does the tetrahedron have (4); the square-based pyramid (5);
the triangular prism? (6)
• Ask three children to make one tetrahedron and two square-based pyramids with
interlocking tiles.
• Ask pairs to compare the tetrahedron with the square-based pyramid by looking for similarities in
and differences between the two shapes.
• Say: The tetrahedron is a regular polyhedron because each face is a regular polygon, all the
faces are identical and the same number of faces meet at each vertex.
• Establish that the square-based pyramids are identical. Remove the square from each shape and
join the eight equilateral triangles to form an octahedron.
• Say: Tell your partner the number of faces and vertices an octahedron has. (8 faces and
6 vertices)
• Ask: Why is it a regular polyhedron?
• Say: We now have two regular polyhedra: the tetrahedron with four faces and the octahedron
with eight faces.
• Point to the shapes in Slide 1 and ask: Who can find the regular hexahedron among this set of
3-D shapes? How many faces will it have? (6)
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Unit 1: Geometry - Properties of shapes
• Say: Tell your partner what we usually call this shape. (cube)
• Ask: Who can explain why a cube is a regular polyhedron?
2
• Display: Slide 2 showing the eight 3-D shapes.
• Ask: Which shapes have all faces right-angled? (cube and cuboid) Some faces right-angled?
(triangular, pentagonal and hexagonal prisms, square-based pyramid)
• Ask: Who can name the shapes that have more than three edges at one or more vertices?
(square-based pyramid and octahedron)
3
• Display: Slide 3 showing the dodecahedron.
• Ask: What can you tell the class about the faces of this shape? (all 12 faces are identical and
each face is a regular polygon)
• Say: Tell your partner how many edges meet at a vertex in this shape. (3)
Individualised Learning
Refer to Activity 2 from the
Learning activities on page 100.
Pupil Book 5A: – Page 22: Identifying 3-D shapes
Progress Guide 5: – Extension, Year 5, Unit 1, Week 3, Lesson 2:
Euler’s rule
Plenary
2
• Display: Slide 2 showing the selection of eight 3-D shapes.
• Ask the children to review what they have learned about 3-D shapes that they did not know
before today’s lesson.
• Ask: What clues might you give to help a friend
identify an octahedron? … a dodecahedron?
• Ask pairs to think of two or three clues which will
identify a 3-D shape and which they will then
present to the class.
Homework Guide 5
Year 5, Unit 1, Week 3, Lesson 2:
About 3-D shapes
Overcoming Barriers
• If children have difficulty in identifying 3-D shapes with right-angled faces from diagrams, allow them to refer to
the solid shapes.
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