Science investigations are being done "by numbers" in schools desperate to improve results, a leading academic claims today.
Writing in The TES, Jonathan Osborne, professor of science education at King's College, London, said that the pressure to do well in assessment meant that coursework investigations were now taught as a set of "recipe-like steps" that have very little to do with proper scientific exploration.
His criticisms come as GCSE coursework continues to excite controversy: a survey by the largest teachers' union released this week found that six out of 10 teachers believe it has added too much to their workloads.
At GCSE, Professor Osborne says assessment of investigation is dominated by just three experiments: measuring the resistance of a wire, the rates of a chemical reaction and the rate of osmosis in a potato.
"How can such a limited set of practicals develop or exemplify the wide range of skills and scientific practices that constitute science?" he writes.
"It's a bit like reducing the teaching of performance in music to three standard scales on a recorder. Any teacher with even half an understanding of science knows that this approach... bears as much relation to science as painting by numbers does to art."
Professor Osborne's comments come with King's College half-way through a series of seminars for the Royal Society aiming to investigate the strengths and weaknesses of current science assessment.
He said that it was becoming clear that assessment was having a "malign" effect on students' and teachers' enjoyment of science and adding to its difficulties.
The survey by the National Union of Teachers, which covered all GCSE, AS and A-level subjects, found that despite serious reservations, only one out of eight wanted GCSE coursework scrapped entirely. But 62 per cent of the 1,707 NUT members surveyed said that coursework had added too much to their workloads.
Most teachers viewed the retention of coursework in some form as essential.
But some admitted that pressure was put on them by senior managers to extend coursework deadlines, or that coursework favoured middle-class students, who were more likely to get "support" from parents.
A review of 14-19 qualifications led by Mike Tomlinson, the former chief inspector of schools, is pushing for most conventional coursework to be scrapped in favour of a new teacher assessment-based system.
John Bangs, the NUT's head of education, said: "We need a radical re-think of the role of coursework. It's become something of an arid exercise, more about rule-following than stimulating young people's imaginations. It needs a new start under Tomlinson."