By Doff, Adrian, Jones, Christopher, Mitchell, Keith
By Timothy P. Bayliss-Smith, Bayliss-Smith, Timothy P.
By Underhill, Nic
By Susan Owens, Peter L. Owens, Owens, Susan, Peter L.
By School Mathematics Project
By Corbett, Jim
By Penny Ur
By Veronica Clark, Clark, Veronica
By Stephen Bell, Peter Brown, Steven Buckley, Bell, Stephen, Brown, Peter, Buckley, Steven
By Roland Soper, David Sparks, Soper, Roland, Sparks, David
By Wes Magee
By Roy Edwards, Mary Edwards, Alan Ward
By Judith Baxter, Baxter, Judith
By Colin Goldsmith, David Nelson, School Mathematics Project
By Brian Bolt, Bolt, Brian
By Jeffrey Wood, Lynn Wood
By Rob Childs
By Paula Bartley, Cathy Loxton
By Alan Millard
By Mike Savage, Julian Williams
By New Horizons Science
By Hashemi, Louise, Thomas, Barbara
By Beryl Austoni, Penny Lucas, Austoni, Beryl, Lucas, Penny