While the conclusions in a report by the pressure group Save British Science are not new, the survey shows that as many as 73 per cent of schools do not have enough money for larger pieces of laboratory equipment and around half (51 per cent) are cancelling practical classes because their labs are not kitted out properly.

But John Richardson, director of the Scottish Schools Equipment Research Centre, pointed out that only 16 per cent of state and independent secondary schools were included. “Those who are broadly happy with the way things are are unlikely to respond to such a questionnaire,” Mr Richardson said.

However, Rosemary Davies of Save British Science, which has carried out a similar survey in England, commented: “We are confident that this is a genuine problem because we collected information from 69 schools across Scotland, and then discussed the issues in detail with a smaller group that represented the cities and rural areas and the north and the south.”

Mr Richardson remarked: “No one is disputing that the patient is ill. The question is what to do bring about a recovery.”

Previous findings in Scotland, notably from surveys by Stuart Farmer, head of physics at Robert Gordon College in Aberdeen, have revealed lack of investment and resources for science teaching - despite pound;18 million allocated by the Scottish Executive in various ways.

But there has been scepticism about whether all of the extra cash finds its way out of complex grant arrangements for local authorities and into science classrooms. Mr Farmer’s investigations suggested that part of the blame might lie with the decisions taken by senior school managers.

Mr Richardson said there is a feeling that science in some cases may, perversely, be no better off as a result of the additional investment because headteachers take the view that it is already generously dealt with. “So we have the old cliche that it’s a case of giving with one hand and taking away with the other,” he said.

There may also be a mismatch between school development plans and allocation of funds by school managers, Mr Richardson said. “Schools which ploughed funds into ICT could put their hand on heart and say that is the money for science and technology.”

The Save British Science survey took issue with the way funds are allocated to schools on a per capita basis which it fears disadvantages small and rural schools. It favours distribution per laboratory.

The survey also covered issues around teaching and assessment and found concern among 86 per cent of science teachers about how the practical element of science is examined. It suggested that students’ skills are not being stretched, and there is often teaching of “poor science”.