The growth is being put down to the Further Mathematics Network, a Government funded scheme which allows students to have lessons out of their school or college. They can be tutored at local universities or other schools or colleges. Sometimes, a tutor from outside their school will visit it to give them lessons there.

Mathematics in Education and Industry ran a pilot in 2000. The independent curriculum development body felt action was needed because with so few students opting for further maths, headteachers found the course uneconomic to run and struggled to find sufficiently qualified staff to teach it.

Emma Cooke, 18, has benefited, having been the only student at De Lisle science college in Loughborough, Leicestershire, interested in taking the further maths A-level. She hopes now to read the subject at Warwick University.

For two years, she spent one afternoon a week at Loughborough University and her tutor visited her school once a week for a two-hour lessons. Emma also worked through online support materials.

She said: “The Further Maths Network is brilliant. I could not have studied further maths without it, and that would have been such a shame. Getting into university would have been much harder without it.

“If I had not studied it, I would also have found normal maths A-level much harder.”

John Sleath, head of maths at De Lisle college, said pupils also benefited from studying at university before going as undergraduates: “You can’t put a price on that experience.”

Celia Hoyles, chief mathematics adviser to the Government, said: “The increase in A-level further mathematics in just three years is an astonishing achievement.”