This practical guide to children's common errors and misconceptions in mathematics is ideal for primary trainees, helping them gain a deeper understanding of the difficulties encountered in mathematical development. This Second Edition has been fully revised and all links to the EYFS and the Revised Primary Framework have been updated. New research and literature are included, additional errors are considered, and using and applying mathematics is fully embedded throughout. Individual misconceptions are dealt with and in each case a description and explanation of the error is provided. The teacher's role in understanding and addressing common misconceptions is also covered.