Just a few years ago, the International Baccalaureate (IB) was seen as an exotic foreign interloper, offered by high-achieving (and high-charging) private schools to a largely expatriate clientele.

Things have changed. As the Government phases in the new 14-19 diplomas aimed at making school-leaving qualifications more practical and relevant to work, it is also looking again at what the baccalaureate can offer.

In 2006, Tony Blair announced that he would make pound;2.5 million available to ensure that there was at least one school or college in each local authority able to offer the course by 2010.

Local authorities are asked to identify a suitable institution, and the Department for Children, Schools and Families offers each one pound;26,000 towards the cost of registration and accreditation with the International Baccalaureate Organisation (IBO). So far, 41 local authorities have taken up the offer.

It highlights a growing recognition that the baccalaureate, with its wide curriculum, may not only deliver a more accurate measure of academic achievement than A-levels, but also simply be a better way of delivering high-school education.

The growth in schools offering the IB suggests it has found favour with teachers. Only a handful of British schools offered it in the early 1970s. This year 126 will, including 52 maintained schools. And the number is forecast to grow to 200 over the next few years.

The IB diploma, which is taken as a school-leaving qualification equivalent to A-levels, is a two-year course usually started at 16. Teenagers who get reasonable grades at GCSE can switch to the course without difficulty. What it does not particularly suit is the highly specialised child, for example a mathematical genius who has no interest in the humanities.

Students select one subject from each of six groups - a first language, a second language, experimental sciences, mathematics and computer science, the arts and individuals and societies (history, for example) - and study them at different levels of difficulty according to their own strengths.

There is a 4,000-word essay on a topic of their choice, a paper called “theory of knowledge”, which explores the business of how one learns, and a community service element. This could take the form of coaching younger children or helping in the wider community.

To English minds it may seem a dauntingly wide curriculum, but on the Continent it is a given that students staying on at school to 19 will do some maths and science.

It provides an all-round education, say its advocates.

Catherine Dobson, director of sixth form and assistant head at Tonbridge Grammar in Kent, says the school decided to offer the baccalaureate in 2004 to provide choice and increase the intellectual challenge for students. Now a quarter of the sixth form choose it.

“We are committed to personalising student learning,” she says. “The diploma means that students who excel in a range of subjects maintain breadth and keep their options open.”

The international perspective it offers and the fact that it has international recognition are particularly valuable for those students looking to work or study overseas.

Many teachers welcome the chance that teaching the baccalaureate offers them to get away from perpetual testing. The diploma is awarded for a combination of final exam and coursework.

Critics, however, say that breadth comes at the expense of depth and the emphasis on synoptic analysis - comparing themes across world literature, for example. The detractors also claim it requires too great an intellectual maturity for many otherwise capable students, and it discourages them from careful analysis of texts.

Another contentious issue has been whether certain university degrees, particularly medicine or some sciences, require specialisation not offered by a baccalaureate diploma.

Jill Rutherford, who advises Oakham School in Rutland on the diploma and is director of Ibicus, a company which runs training courses for baccalaureate teachers, says this is not so.

“The only degree the diploma would not combine with is Cambridge maths,” she says.

“For greater specialisation it is easy to drop, say, one arts course and substitute an extra science.”

Unfortunately, the hardest course for a school to steer is to try to offer both A-levels and the baccalaureate.

“The baccalaureate cost per student is about double that of A-levels,” says Ian Andain, the head of Broadgreen High in Liverpool (see panel, right).

“There are the registration costs, staff training, the annual fee to the IBO, and the cost of hiring a co-ordinator and someone to run the community programme. The Government’s pound;26,000 covers only start-up costs.”

For this reason, Broadgreen High has now dropped A-levels and offers either the baccalaureate or vocational qualifications.

Baccalaureate enthusiasts argue that staff retraining is one of the best parts. The IBO requires a proportion of those teaching the diploma to attend regular refresher courses at the organisation’s headquarters in Geneva.

The biggest caveat, teachers say, is to remember that baccalaureate students’ workloads are heavier, simply because of the number of subjects studied.

“You need to be careful that you don’t overload them,” says Mrs Rutherford at Oakham School.

“But remember also that you shouldn’t need to. These students are learning to learn much more independently than before. They should know how to research something for themselves, without you spoon-feeding them.”

HOW TO BECOME A BACCALAUREATE SCHOOL

There are three stages involved in registering and being approved to deliver the IB.

1. The school applies to the IBO through its British offices in Bath or Cardiff to become a “candidate school”. This may take six months.

2. It sets up its IB programme, guided by the organisation’s regional office. This usually takes one academic year.

3. The school submits a formal application. There follows a visit by IBO officials. If approved, formal teaching can start.

After three years, the school will be asked to submit a self-review and will be visited again. Subsequent inspections are every five years.

Costs vary, but start-up fees come to about pound;10,000, plus staff training.

- www.ibo.org

THE DIPLOMA THAT WENT INTERNATIONAL

The IB diploma was created in 1968 by teachers from international schools around the world, led by Scot Alec Peterson, who became the first director-general of the International Baccalaureate Organisation (IBO), based in Geneva. Programmes cater for children aged 3-19: primary years, middle years and the diploma programme. About half a million students from private and state schools in 126 countries study an IB programme. The UK has the third largest number of schools offering the IB - 126 - after the USA and Canada. The first school in Britain to adopt the IB was the United World College of the Atlantic in Wales, a private boarding sixth form college.

The IBO is a non-profit body, which relies on exam and annual school fees. The examiners are usually teachers, overseen by a senior university academic.

IN PRACTICE

The IB has given us a new lease of life

Ian Andain, head of Broadgreen High in Liverpool, introduced the International Baccalaureate to the sixth form in 1992 and says he has never looked back. “Personally, it’s been fantastic,” he says. “I’ve been a headteacher for 18 years and it has given me a new lease of life.

“My colleague heads in Liverpool thought I was mad at the time. But the quality of both teaching and learning at Broadgreen High has improved tremendously.”

Broadgreen High is a typical inner-city comprehensive. Many of its 1,300 pupils are entitled to free school meals, and it has a significant proportion of special educational needs children. Yet Mr Andain (above) says the baccaulareate has attracted excellent staff and totally changed the character of the school.

Of his 190 sixth-form students, 65 are taking the IB. The rest are doing vocational programmes, but all benefit. The community voluntary service required for the IB diploma improves the ethos of the whole school and has helped social cohesion in an area of urban deprivation, says Mr Andain. So has the international flavour lent by children whose parents have come from overseas to work in the UK, and have chosen Broadgreen High because it offers the IB.

Mr Andain believes that far from being suitable for only high-achieving, academic students, it fosters the very skills the Government says it wants to encourage in teenagers to make them ready for work or tertiary education.

He says: “I see them developing the sort of skills that matter to employers and universities. The diploma requires students to learn to think for themselves. The extended essay needs independent research and the power to develop an argument, and they are also required to make presentations as part of coursework.”

Mr Andain also refutes the perception that the diploma is too demanding for less able students, arguing that those who cannot obtain a full diploma can still expect to be offered a university place somewhere with whichever certificates they can achieve in individual subjects.