The government must set up an independent body responsible for curriculum reform to protect science education from the "assault" of politically driven change.
This is the verdict of a hard-hitting report published today by the Royal Society, the world's oldest scientific academy.
It argues that England's schools have suffered from "politically motivated, knee-jerk reactions and constant change", which have done little to increase the numbers of youngsters taking sciences post-16.
UK schools are failing to provide the number of school-leavers with science qualifications needed by Britain's economy. And the number of maths and science teachers has fallen in the past 10 years.
In its state-of-the nation report on science and maths education, the society produces figures which show that the number of 17-year-olds taking biology, chemistry, physics and maths, measured as a proportion of total entries, shrank between 1997 and 2007.
While absolute numbers of students taking biology and chemistry grew over that time, they fell in physics and maths. The overall number of A-level students rose by 22 per cent over the same period, meaning that in all four subjects there was a drop in the proportion studying them.
This summer, there has been an increase in the numbers taking all four subjects, although this barely affected the proportion taking the sciences. These figures are not included in the report.
The society highlights several science reforms that it argues were not subject to proper trialling, including GCSEs launched in 2006 and taken for the first time this summer, and the new science diploma, to be launched in 2011.
It also says that the introduction of the national curriculum in 1988 was dominated by "rushed initiatives and ad hoc responses"; that the Government's new diploma qualification "might be cited as another example of a process with an unclear and unstable rationale"; and that other vocational courses have been too politicised and not trialled properly.
The society contrasted all of this with the development of Scotland's Curriculum for Excellence, which it said had been more "measured". Reform in Northern Ireland and Wales lay somewhere between the hectic pace of change in England and Scotland's more cautious approach, it said.
Professor Michael Reiss, the society's director of education, said: "Science and mathematics education, particularly in England, has been assaulted by reform over the past 20 years.
"Recently there have been encouraging signs that more young people are choosing to study the sciences after the age of 16, but the longer-term trend exposes the failure of the many changes to make enough of a difference.
"Unless we break the cycle of politically motivated, knee-jerk reactions and constant change, we are in danger of never giving reforms the time to bed in, and therefore not getting to grips with what works and what doesn't."
The proportion of A-level entries in England taken in biology fell from 7.2 to 6.5 per cent in the period 1997-2007; in chemistry from 5.5 to 4.9 per cent; in physics from 4.3 to 3.3 per cent; and in maths from 9.2 to 8.1 per cent.
Again the report contrasts this with Scotland, where 13 per cent of 17- year-olds sat Scottish Highers in biology and chemistry; 12 per cent in physics; and 28 per cent in maths in 2007.
In contrast with the overall trend, English entries in psychology - which the report said was perceived both as popular and easier than the other sciences - doubled from 3.4 per cent to 6.8 per cent, which may partly explain the falls in other sciences.
The report also criticised the exam boards Edexcel and Cambridge International Examinations for refusing, on the grounds of commercial confidentiality, to release information on the number of pupils taking their Btec and international GCSE courses.
A Department for Children, Schools and Families spokeswoman said: "Recent exam results show that our reforms are having a positive impact. The number of young people taking maths and science A-levels continues to increase, and this year the number taking maths A-level was the highest for a decade.
"We want to see even more progress, though, which is why we are investing millions promoting science and maths as options."