TOPIC
28
3D Shapes
442
443
444
445
446
Strand: Shape and Space
Strand unit: 3D Shapes
Identify, describe and classify 3D shapes, including cube, cuboid, cylinder,
cone, sphere, triangular prism and pyramid.
Establish and appreciate that when prisms are sliced through (in the same
direction) each face is equal in shape and size.
Explore and describe the relationship of 3D shapes with constituent 2D shapes.
Construct 3D shapes.
Solve and complete practical tasks and problems involving 2D and 3D shapes.
Looking back: What the 3rd class programme covered
1. Identify, describe, classify and construct 3D shapes, including cube, cuboid,
cylinder, cone, sphere, triangular prism and pyramid.
2. Explore and describe the relationship of 3D shapes with constituent 2D shapes.
Maths skills used in this topic
1. Reasoning: Reason, investigate and hypothesise with patterns and relationships in mathematics.
Models or examples of 3D shapes, card for nets
Vocabulary
Cube, cuboid, cone, cylinder, sphere, prism, pyramid
Teaching points
1. For the cross-section/prism activities, show the students a tree trunk that has been sawn
through. It will be easier for them to understand the concept of cross section. Annual rings on
a tree trunk might make for an interesting nature discussion.
2. Make shapes from cubes, counting the number of cubes used. If the shapes made are cuboids,
we can examine features such as: How many cubes in each row? How many cubes wide is the
shape? How many cubes high is the shape?
Split the children into pairs and give each pair a 3D shape. The children have to
discuss the properties of the shape. For example: How many sides/corners/vertices/
edges/faces it has. Will it roll? Will it stack? The children can then describe their
shape to the class.
106
Topic suggestions
1. Creating 3D shapes from nets is a fun activity and could double as an art lesson.
Use card if possible. Some nets have tabs to make them easier to tape together.
2. The children will also enjoy creating 3D images on paper:
(a) Draw a simple square.
(b) Move to the left and down and draw another square
the same size as the first.
(c) Connect corresponding corners.
3. 3D shapes can be made as frames using lollipop sticks. Blu-tac or any putty like material will
serve at the corners to join the sticks.
4. Page 170: Ask the children to look at the slices in each picture. Are the slices the same size?
(Ignoring the width – you want the children to distinguish whether or not the slices have the
same dimensions (prism) or whether they’re getting progressively smaller (pyramid)).
Activity A
Nominate each shape in turn and ask questions such as:
1. Describe the shape.
2. How many faces/edges/corners (vertices) does it have?
3. What might this shape be used for?
4. Where have you seen this shape?
5. This is a 3D shape – with which 2D shape(s) might it be matched?
6. Do you think it’s possible to stand it on its side?
7. Do you think it’s possible to stand it upside down?
8. Does it roll?
9. Will it stack?
Differentiation
Lower attainers:
Pupils can assemble the pentagonal prism from the photocopiable templates.
Higher attainers:
Related shapes and activities. Ask the children to research how
cylinders (tree trunks) may have been used long ago to transport
very heavy objects before the wheel and axle were invented.
They could also examine the wedge and its uses. A wedge has
5 faces, 9 edges and 6 vertices. One use made of the wedge
shape was to help in building tall structures in which heavy
stones had to be transported to a height. The wedge acted as a
ramp (related: wedge of cheese, door wedge, golf wedge, wedge
heels, etc.)
Linkage
Shape and Space: 2D shapes
107
Integration
SESE Visual arts: Constructing 3D shapes
Maths at home/parental involvement
Find an example of 5 3D shapes at home and describe what each is used for. Try to find
unusual examples: perfume bottles, candles, drinking glasses, mobile phone, curtain pole, door
knob, paperweights, food containers and packages, bar of soap, alarm clock, etc. Bring some
examples into school if possible.
Notes
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
108