How many hours of science and for whom?: The question is dividing parents, teachers and pupils. Karen Gold looks at both sides of the debate

Do you need to study science for five hours a week to decide which fertiliser to put on your garden? Parents, school governors, headteachers and pupils will soon be faced with this question, as the campaign to keep a high profile for science at GCSE gathers pace.

Under the present national curriculum, all state school pupils must study combined biology, chemistry and physics - known as 'balanced science' - from the ages of five to 16, and 14- to 16-year-olds are expected to spend at least 12.5 per cent of their school week doing science. In that time they will cover topics required to get one GCSE. In fact, most pupils now spend 20 per cent of their week doing science, and gain double GCSE science.

The single science option should remain the minimum compulsory science for all children, Sir Ron Dearing said in his recent review of the curriculum. It seemed an uncontroversial reiteration of the status quo. Yet august pro-science bodies such as the Royal Society immediately protested.

Their worry, according to Robert Rees, the Royal Society's education officer, is that instead of single science being the choice of a small minority of pupils, it could become the norm. The single science syllabus, he says, was introduced to cater for a handful of children with special talents in music and languages, who could not fit double science into their week.

Since those were among the brightest children, the single science syllabus was intended to offer a fact- packed grounding. Schools that offered this single science course -the only one available under the national curriculum - to lower ability pupils, hanging on to old beliefs that bottom streams were incapable of much science, found the single science course so unpopular that they soon switched to double science for all, Mr Rees says.

But the Dearing report not only encourages wider choice at 14 but also promises to make the single science syllabus attractive and manageable in 10 per cent, rather than 12.5 per cent, of the school week. 'It was all right so long as as the system showed the benefits of the double award and encouraged most pupils to go down that route,' Mr Rees says.

'But if we move to a culture of choice rather than compulsion, and single science becomes a more popular course, then we are concerned that there may be a gradual drift to single science as an acceptable mainstream option.'

So why is single science not enough? After Easter the Royal Society will leaflet every school, putting its case that pupils need to study double science not only as the minimum base for science A-levels but also to qualify them for citizenship and daily life.

'We simply believe that in an increasingly scientific and technological society, all students should be entitled to have sufficient backgrounds in science to take decisions about scientific issues that affect their lives - like the genetic programme, or what fertiliser to put on their garden,' Mr Rees says.

The country needs scientists, and 14- year-olds are too young to opt out of the minimum scientific training necessary for science A-levels and a scientific career, says Dr David Moore, of the Association for Science Education.

Science educators would prefer anyone considering a scientific career to have spent 30 per cent of their GCSE time on science, he says. But when the national curriculum was drawn up, they reluctantly accepted the argument that children should study a wide range of subjects up to 16: 'So we feel we've made our reduction already.'

In return, Dr Moore says, offering every child a broad menu of balanced science was intended to interest many in subjects they had previously hardly considered, and thereby to reverse the flight from science A-levels and science degrees.

This summer, when pupils taking GCSEs will have studied balanced science since 11, will be the first chance to see if the experiment has worked, Dr Moore says. 'It is unbelievable that any change is being contemplated now, before it has had a chance to show its effects. We have never been so close to seeing the benefits.'

----------------------------------------------------------------- GCSE SCIENCE OPTIONS ----------------------------------------------------------------- Balanced science: an equal mixture of biology, chemistry and physics. Double science: five hours a week of balanced science, leading to two GCSEs. (This is what most pupils have been doing for the past four or five years.) Single science: two and a half hours a week of balanced science, worth one GCSE. (More pupils may do this as a result of the Dearing report.) Triple science: seven and a half hours a week of balanced science, worth three GCSEs. (This will be available from next year.) Separate science: stand-alone physics, chemistry and biology, still often taught in private sector but only in 3 to 5 per cent of state schools. -----------------------------------------------------------------

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