Lead author Tony Cotton is a writer and educational consultant with over 30 years teaching in primary schools, secondary schools and Universities. He is the author of a number of books including Understanding and Teaching Primary Mathematics. Caroline Clissold is an experienced teacher, having taught all years form Years 1 to 6. For nine years, she was the mathematics consultant for a London borough responsible for implementing the national numeracy strategy. She now conducts teacher training workshops and her main interest lies in developing ways to integrate speaking and listening skills in a meaningful, engaging way. For the last ten years Linda Glithro has been Deputy Head in a large independent school with particular interest in Maths, Science and assessment. Previously she has also worked in primary schools across Oxfordshire and was a founding member of the Maths Association Primary Sub-committee.