Making connections - Proportional Sets

The images of photographic enlargements and shadows provide contexts to help pupils to make links between numerical work on proportional sets of numbers, scaling multipliers and geometry.

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
- and making the link to proportional sets of numbers.

Use tried and tested classroom resources to develop and use these images:
  • Geometrical images of scaling– Teacher notes and resources
  • Photographic enlargements – Interactive Teaching Program (ITP) and accompanying ‘How to use notes’

What do the resources include?
The resources draw on the images of photographic enlargements and shadows to support exploration of relationships between ratios of dimensions within and between shapes.
All resources are available as teacher notes and resource sheets, one is also available as a computer application:

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 photographic enlargement image´┐╝

Photos


Example of shadow images

Shadows