Key Stage 3
Measures, Shape & Space Dimension
Learning Unit：Transformation and Symmetry
Learning Objectives :
•recognize reflectional and rotational symmetries in 2-dimensional (2-D)
shapes
•recognize the effect on 2-D shapes after the transformation including
reflection, rotation, translation, dilation/contraction etc.
•appreciate the symmetrical shapes around and transformations on shapes
used in daily-life
Programme Title :Transformation and Symmetry
Programme Objectives
- Recognize reflectional symmetry, both vertically and horizontally, in 2-D shapes.
- Recognize rotational symmetry in 2-D shapes.
- Recognize 2-D shapes with properties of both reflectional symmetry and rotational symmetry.
- Recognize the effect on 2-D shapes after the transformation including reflection, rotation, translation, dilation/contraction etc.
- Appreciate the symmetrical shapes around and transformations on shapes used in daily-life
Programme Outline
In the programme, three young designers show their appreciation of the regularity and configuration of geometrical shapes which serves the purpose of developing students’knowledge in plane geometry and promoting their interest in mathematics.
They introduce the basic concept of symmetry and elaborate the idea of reflectional symmetry and rotational symmetry in 2-D shapes. Common objects with symmetry shapes and the use of symmetrical shapes to form patterns and drawings in daily-life are also shown in the programme.
Other daily-life examples such as mirror images, human-like figures, pedestrian on moving walkway and on escalator, image projected from overhead projector andshapes for checking eyesight are used to illustrate the effectson shapes after transformation including reflection, rotation, translation and dilation/contraction.The relations of the shapes, sizes and orientations between the object and its image are discussed.
Through an intuitive approach, the programme helps to develop students’ deductive reasoning in learning geometry.
Worksheet Answers
1.2 axes of symmetry
2. infinitely many axes of symmetry
Key Stage 3 ETV Programme《Transformation and Symmetry》
Worksheet
1.How many axes of symmetry does a rhombus have? Draw the axes of symmetry on the diagram.
2.How many axes of symmetry does a circle have? Draw the axes of symmetry on the diagram.
3.(a)Design a simple figure and then draw another figure which is symmetrical (reflectional symmetry or rotational symmetry) to the first one.
(b)Use the combined shape of symmetry in (a)to form a pattern.
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