The Sheffield report suggests that the percentage of 16 to 19-year olds who are functionally innumerate has remained at around the same level for at least 20 years (“20% leave school ‘functionally illiterate and innumerate’”, May 7).

This report follows other reports, including one by Ofsted in 2006, which suggest that mathematics education is not working for a significant percentage of pupils and points the finger at the predominant pedagogy of teaching maths by rote learning rather than by understanding.

The research into learning difficulties in maths identifies the key contributing factors as: working memory, retrieval of basic facts, speed of working and the ability to solve word problems. If maths is taught without active regard for these factors, then it will not work for the 22 per cent who are functionally innumerate.

Understanding and interlinking concepts and facts can support memory. Dealing with the inconsistencies that are so pervasive in early maths and starting each new topic where the learner is secure will enhance learning.

Steve Chinn, Author and consultant in maths and learning difficulties.