Ofqual is going ahead with its controversial plan to stop practical work from contributing to overall science GCSE grades, despite strong opposition from government and much of the scientific community.

The exams watchdog insists that separating science practicals from high-stakes assessment will actually improve the variety and quality of hands-on science work in schools.

But the decision has placed the regulator on a collision course with education secretary Nicky Morgan, who warned that the plan, together with a similar scheme at A-level, was “in danger of holding back the next generation of scientists”.

Ms Morgan has now written to Ofqual insisting that it should revisit the decision if it has a “detrimental effect”. “I continue to share the concerns of many in the science community that not having an assessment of practicals as part of the GCSE risks undermining the teaching of practicals in schools,” her letter says.

Last night a Department for Education source told TES that Ofqual’s entire role was “under review”. Ministers were “deeply unimpressed” and could legislate to overturn the move if they were in power after the election, the source added.

Ofqual said that four-fifths of respondents to its consultation supported the new arrangements, which will leave GCSE assessment concerning practical work confined to written exam questions.

The changes will come in when new science GCSEs are introduced for first teaching from September 2016.

The watchdog’s chief regulator Glenys Stacey said: “We have consulted widely and have identified a new approach to the assessment of practical science that will liberate teachers to offer a wider variety of classroom experimentation and promote effective student progression to further study or employment.”

Ofqual, which has yet to release the detailed consultation results, has also claimed “enormous support” from teachers for the changes, which will require science GCSE students to complete a minimum of eight different practical activities.

But several leading scientific organisations fear the result in many schools will be a downgrading of practical work and facilities. They include the Wellcome Trust, which did not respond to the consultation because it did not believe Ofqual would change its mind.

The charity’s head of education Hilary Leevers said: “If you don’t include a measure of pupils’ ability to do science in a science GCSE, then it is not what I would really call a science GCSE. It is science knowledge or science theory or whatever you might want to call it. But to me so much of science is what you can do and that will not be reflected at all in the GCSEs.”

TES understands that relations between Ofqual and the Department for Education, already poor after the watchdog’s handling of a row over GCSE maths standards, have reached a new low.

The DfE source said: “We believe that Ofqual fulfils an important function but we keep their role under review. We have been deeply unimpressed with the way that Ofqual has handled this [GCSE science practicals]…If we get any indication that this move is having an impact on practical teaching or the uptake in science subjects then we won’t hesitate to legislate in the next Parliament.”

Related stories:

Science practicals plan will end ‘Fawlty Towers’ assessment, Ofqual insists February 4 2015

Exam boards stick to science plans despite government criticism - January 28 2015

Ofqual seeks to ensure all things are equal in maths - January 23 2015

The TES Podcast - science practicals - January 16, 2015

Ofqual: science practicals will no longer count towards GCSE grades - December 10, 2014

Practical science to be removed from A levels due to fears of cheating and over-marking - October 25, 2013