By School Mathematics Project
By School Mathematics Project, Unnamed
By Bolt, Brian
By SPMG, Scottish Primary Maths Group
By Straker, Anita
By Gardiner, Tony
By Neill, Hugh, Quadling, Douglas, Quadling, Douglas
By Harrison, Paul, Mumford, Jeanette
By Kirkby, David
By Straker, Anita, Anita Straker
By Atkinson, Sue, Harrison, Sharon, Rousham, Laurie
By Norman, L. C.
By Snape, Charles, Scott, Heather
By Phillips, Richard
By Eagle, Ruth