His wisdom is founded on membership of a remarkable TLC of maths teachers at the start of his teaching career. It was called Smile (Secondary Mathematics Independent Learning Experience) and it nourished a large number of us, enabling us to change our practice in the way he describes to create TLCs in classrooms where study was based on careful assessment, and planned to suit individual pupils.

However, Smile was gradually strangled by legislating politicians. What could have been the final nail in the coffin has been hammered in by the borough of Kensington and Chelsea, which closed the project down, with copyright over its archives.

Now a group of 20 to 30 ex-Smilers plans to form an educational trust so the rich resources we created can again help maths education.

Jan Allcorn Mathematics consultant

Jacqui Bowers Acting director of Smile

Rachel Gibbons ex ILEA maths inspector

John Hibbs retired HMI

Peter Osmon Emeritus professor of computing, City University