Kids - don't you just love 'em! When Prime Minister Tony Blair chose Oxford as the place to launch a keynote speech about the importance of science, his specially invited audience poured cold water on his ideas. Students at Cheney School who listened to his speech - about how British scientists were now more successful at taking their discoveries from laboratory to marketplace - told The Oxford Times afterwards that it would put them off studying science at A level, rather than encourage them.

If there's one thing that bores today's schoolchildren more than science, it's business, manufacturing and production processes. Which child ever grew up wanting to work in a factory or office? When you look at young people's career choices, most of them fall squarely into three camps - idealist (doctor, nurse or charity worker); passion (horses, children or engine driver); or making oodles of money. It was this last motive that Tony Blair was perhaps attempting to tap into. But in a week when the pay analysts Incomes Data Services (IDS) said the country's top 100 company executives now earn 98 times more than all full-time workers, today's schoolchildren quite correctly guess that studying accountancy or finance is a more likely route to riches than science.

Those of us old enough to remember the last time that a government chose to bring science to the forefront of policy are also sceptical. I was a naive member of the United Nations youth wing when Tony Benn talked about the "white heat of a technological revolution". I was inspired to take double maths and physics A levels in the belief that science could help solve some of the world's problems, creating food for the starving millions and prosperity all round.

Today's British youngsters no longer worry about unemployment - something for which the Prime Minister must surely thank Gordon Brown. During the intervening years, science has left us a legacy of nuclear waste which will take many generations to become safe, and developed clever cancer drugs which are so expensive that the National Health Service cannot afford them. Then there is climate change - the result of just a few decades of industrialisation. Is it any wonder that exam students are wary of science?

However, despite the falling numbers of A-level science students and the closure of several university chemistry departments, British science is generally in good shape, with its budget more than doubled over the past decade. Mr Blair was in Oxfordshire to congratulate scientists at the Diamond Light Source, at Harwell, on reaching the final milestone of the UK's biggest science project for 30 years. They have succeeded in focusing the light source into an intensely powerful beam and delivering it to three experimental stations, where it can be used to study the structure of matter. The 'supermicroscope' - known as a synchrotron - cost £250m, of which the Government paid 86 per cent and the medical research charity Wellcome Trust paid 14 per cent.

Mr Blair said: "This new world-class facility shows the importance this country attaches to science and scientists. Our future prosperity rests more than ever before on the hard work and genius of our scientists and how we harness their research to deliver improvements in all our lives.

"This is exactly what Diamond Light Source will help us achieve in many fields, from developing new drugs to tackling climate change."

On the day he arrived, climate change was high on the agenda, as Greenpeace campaigners scaled the iconic cooling towers of the coal-powered Didcot Power Station, complaining about the Government's lack of action on cutting carbon dioxide emissions. Mr Blair is no doubt hoping that Diamond will help Britain to develop 'green' fuel sources - or at least some better building materials for our badly-insulated homes.

Chairman of the Diamond Users, Prof Trevor Rayment, had some cheerful news for the Prime Minister about Diamond, which is the size of three football pitches, and looks a bit like a giant doughnut or sporting stadium. Prof Rayment told journalists: "Unlike Wembley, it was built on budget and on time - at about a third of the cost, and it's above specification. It's a lab where world-class scientists can carry out premier league science, and you can trust that we will."

In a classic case of "synergy" between government and industry, many of the optical components were made by Oxford Danfysik, based in Osney Mead, which is a worldwide expert in the specialist technology of beamlines. Formerly Oxford Accelerators, the company was bought from Oxford Instruments in January 2001 by Danish company Danfysik. Its components are used in synchrotrons worldwide, including the European Synchrotron Radiation Facility in Grenoble, France, where many British scientists are basing their research while they wait for the Oxfordshire machine to be completed.

With climate change still on his mind, the Prime Minister paid a surprise visit to Regenatec, next to Didcot Power Station at Milton Park. He rode on the park's shuttle bus, which is powered from plant oil, creating less emissions than diesel. He was told that if all HGVs, buses and light goods vehicles in the UK converted to the technology, the Government could meet its targets under the Kyoto agreement, cutting nine million tonnes of carbon dioxide emissions a year.

Regenatec's founder and managing director, Mike Lawton, introduced the Prime Minister to two of the company's lead customers - David Giles, of Accord, which works with local councils and the Government's own Highways Agency; and Keith Abel, founder of Abel & Cole, the country's largest organic home-delivery supply service. Mr Blair was impressed to hear that Regenatec has recently converted the UK's first fishing vessel to operate from processed used vegetable oil, using a Government grant. The fishing industry has recently been highlighted as the sixth most carbon-intensive industry, as well as being highly polluting because it uses lower quality marine-grade diesel oil.

Regenatec is working with Oxford Brookes University and "a leading fuel additive manufacturer" to develop a plant oil quality standard acceptable to engine manufacturers.

However, even this 'green technology' has been under fire from environmental campaigners, because rainforest is being cleared at an alarming rate to grow palm oil. Mr Lawton said: "We source our oil from less sensitive areas and actively avoid oils from cleared rain forest. Our current research is heavily focused on using waste' cooking oils. We expect to be in a position shortly to start supplying processed used oils for use in converted vehicles."

The Prime Minister told Mr Lawton he would "look into" one of the industry's main problems - the taxes that mean that green fuels are no cheaper than fossil fuels. And Mr Blair was definitely more in tune with the young Cheney students when he said: "Regenatec represents the many faces of science today - invention, practical application, commercial development and moral impulse."

However, he overlooked one of the biggest attractions of science - curiosity about life, the universe and all that, including exploring things which may have absolutely no practical application. If Mr Blair wants more students to do science A level, he should look at the work of the Oxford Trust, a charity promoting science, which was set up by industrialists Sir Martin and Lady Wood, founders of Oxford Instruments. While "contributing to the economic growth of Oxfordshire" is one of its aims, it also treats science an integral part of our cultural life. One of its projects, exploring the boundaries between art and science, is a giant quilt being made by Womens Institute members in response to debate about the study of diseases, drug development and environmental health using the Diamond Light Source.

Martin Rees, President of the Royal Society, responded to the Prime Minister's speech by saying: "Science education isn't just for future scientists. How science is applied concerns us all since it involves an increasing range of environmental, ethical and economic choices. Genuine public engagement requires a well-informed debate.

He added: "The Prime Minister's effective leadership of the G8 on climate change and other issues shows that the UK government, backed by sound scientific advice, can have real international leverage.

"Earth's optimum stewardship and a just sharing of the benefits of globalisation between the developing and developed world is a goal that resonates with the intellect and idealism of the young. Supplying the entire world with clean low-carbon energy is a massive long-term challenge. I can't think of anything that could do more to attract the brightest and best of them into science than a strongly proclaimed national commitment to take a lead in meeting this challenge. In this country's own interest, the UK should seize the chance to play a pivotal role."