But Tony and Cherie Blair have merely joined the ranks of thousands of other parents who are prepared to pay to ensure their children get the very best out of their education.

Average hourly prices for tuition

Primary pupils: �16 GCSE pupils: �17 AS and A-level: �19 Degree level: �20 An extra �2.50 charge applies if the tutor goes to the pupil's house Source: Top Tutors, London and South East

The rush for places at the best secondary schools, then for good grades to get into the best universities, has led to a boom in personal tuition.

And the new AS-levels, sat for the first time by sixth formers last summer, have put extra pressure on pupils studying a wider range of subjects.

Search on the internet for private tutors or flick through the Yellow Pages, and the lists of agencies seems endless.

Demand is particularly high in London where schools may be set in deprived areas.

11-plus coaching

The Top Tutors agency, based in north London, has experienced a boom since it was set up in 1985.

"We now have 8,000 jobs - individual pupils requiring tuition - a year, that compares to 5,000 three years ago," said founder and director, Bill Fleming.

"We've had to take on new staff to cope with the number of calls and install more telephone lines."

Mr Fleming has seen a big demand for 11-plus coaching, as parents strive to get their children into grammar and private schools which require entrance exams.

"People just want to do the best for their children - if there's just one outstanding school in the area, they just want to try and get their children in," said Mr Fleming.

"In some local schools, you could get as many as 900 applicants fighting for 90 places," he said.

AS-levels

And the advent AS-levels means students are covering an average of five subjects in the sixth form rather than three.

"They're covering more subjects so they may need more tutors, whereas in the old days they did three A-levels , so needed just three tutors," said Mr Fleming.

And, contrary to popular belief, Mr Fleming says it is not just the better-off coming forward for extra tuition for their offspring.

"We get a lot of middle-class parents, but we get parents across the board," said Mr Fleming.

"Some parents struggle long and hard to put the money together."

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