Using Cabri Geometry II in Key Stage 3

by Jack Jackson

Geometry is a dynamic subject, best understood when we discover it for ourselves with a dynamic interactive tool. Cabri Geometry II software is the perfect tool for exploring geometry dynamically. This set of worksheets shows how to use Cabri to explore and understand KS3 school geometry.

Each worksheet is in two parts: the first part provides systematic instructions to set up a robust screen that will demonstrate particular geometrical properties. The second part is an investigation that will lead to the students discovering the geometrical properties for themselves.

They are designed to be used in a variety of ways.

• Used by teachers to set up a screen, which can be saved on a network
  so the student can access it, and so start the investigation immediately.
• Used by students to set up their own screens so that when they start
  investigating they understand the geometrical properties of the screen.
• Used by teachers to set up a demonstration on an interactive whiteboard.

Many of the activities provide opportunities for students to make the first steps towards developing geometrical proof, in the four-step process of: convince yourself; convince a friend; convince a pen-friend; convince your maths teacher. These activities will help with the crucial first step of students understanding the geometry before starting on a recording process that will eventually lead to a written proof.
The activities cover all of the specific examples referred to in the UK’s Key Stage 3 National Strategy Framework for Teaching Mathematics Years 7, 8 and 9, and much more besides. References to objectives in the Key Stage 3 Framework can be found in the last section of the book.

ISBN 1-904506-00-3, 48 pages, photocopiable £20, published by Chartwell-Yorke

Chartwell-Yorke, 114 High Street, Belmont Village, Bolton, Lancashire, BL7 8AL, UK. Tel (+44) (0)1204 811001, fax (+44) (0)1204 811008, email info@chartwellyorke.com, http://www.chartwellyorke.com