Helen Warrell:

The children of cleaners in Asian cities such as Shanghai and Singapore are better at maths than the offspring of doctors and lawyers in the US and UK, according to an analysis of the global Pisa test rankings published on Tuesday.
The international league table, first released by the OECD in December, had shown 15-year-olds in Shanghai to be top in maths, while the UK languished in 26th place and the US in 36th.
But fresh scrutiny has revealed that the state-educated children of British professionals are on average a whole school year behind the children of “elementary” workers in Shanghai in maths ability, and around three months behind the same group in Singapore. The gap is even wider between US professionals and Asian cleaners or caterers.