Making connections between scaling and geometrical images of scaling
The images of cat faces, photographic enlargements and shadows provide contexts to help pupils to make links between numerical work on scaling multipliers and the geometry of scaling and similarity.
You can use the images to identify ‘within’ and ‘between’ aspects of dimensions of shapes, applying ratio and scaling to explore similarity comparing:
- internal dimensions of a shape
- corresponding dimensions between shapes.
- Geometrical images of scaling– Teacher notes and resources
- Photographic enlargements – Interactive Teaching Program (ITP) and accompanying ‘How to use notes’
The resources draw on the images of cat faces, photographic enlargements and shadows to support exploration of relationships between ratios of dimensions within and between similar shapes.
All are available as teacher notes and resource sheets and one is also available as a computer application:
- Teacher notes with suggestions for teaching sequences using each of the three images
- Resources sheets with
- cat faces to which various scalings have been applied
- photographic enlargements for identifying measurements and ratios between corresponding dimensions
- two sets of shadows for calculating missing dimensions by applying scalings
- Photographic enlargements - Interactive Teaching Program (ITP)
- How to use Photo enlargements ITP notes.
How will these resources help pupils?
Develop pupils’ understanding of links between numerical work and geometry:
- the invariant properties of enlargement
- the concept of similarity between shapes.
Example of cat faces image
Example of photographic enlargement image
Example of shadows image
