By Richard Cooper
By Letts KS1
By School Mathematics Project
By Rosie Hore, Luana Rinaldo
By Bill Gillham
By Collins Easy Learning
By Keen Kite Books
By Hilary Schofield & Sims, Koll, Mills, Oxford Designers & Illustrators Ltd
By Gareth Moore, Chris Dickason
By David Glover (Rutgers University), Tim Hutchinson (Larkmead Veterinary Group, UK)
By Math Blue Publishing
By Soper, Sandra
By Clarke, Peter
By Kumon Publishing, Kumon
By Kristie Pickersgill
By Schofield & Sims, Steve Mills, Hilary Koll
By Richard Cooper, Cooper, Richard, Burville-Riley, Mark
By Murphy, Stuart J., O'Malley, Kevin
By Rosie Dickins, Benedetta Giaufret, Enrica Rusina
By Dickinson, Paul, Hough, Susan, Eade, Frank, Gough, Steve, Dudzic, Stella
By Bovey, Jane, Burville-Riley, Mark