New vocational qualifications to provide an alternative to GCSE and transform school life for 14-to 16-year-olds are expected to be announced on Thursday by the Government.

Ministers have decided to run a pilot next year in 90 of 4,000 secondary schools. Courses for under-16s could be available in all schools by 1997. Vocational courses for over-16s have proved extremely popular, and hundreds of schools are thought to have volunteered for next year's pilot.

The General National Vocational Qualification courses are not designed as training for a particular job. They are classroom-based, so a pupil taking, for instance, manufacturing, might do work experience in a local factory but would not have to make anything.

Last week Sir Ron Dearing, chairman of the Schools Curriculum and Assessment Authority, said 40 per cent of the timetable for 14-to 16-year-olds would be freed so that some pupils could pursue vocational courses, while others do the more academic GCSEs. All will continue to do GCSEs in English, maths and science, and short courses in modern languages and technology.

Critics say the arrangements will divide pupils into sheep and goats, and could lead to the creation of specialist academic and vocational schools. Supporters say the new courses will motivate non-academic pupils so that fewer leave school without qualifications.

The new courses in health and social care, business and manufacturing are being introduced despite fierce criticism of present vocational qualifications for over-16s in reports from school inspectors and academics. The inspectors said the course content was too vague and that assessments, done mainly by teachers, were unreliable.

The National Council for Vocational Qualifications, which has drawn up the new courses, has tightened up details of what must be taught and offered more guidance for teachers. It has also agreed that course work should be marked by outside examiners, as well as teachers.

However, the GNVQs will be modelled closely on those for over-16s, which have six units. Pupils will study three of the six, and will also have to reach agreed standards in three ``core skills'' of literacy, numeracy and information technology, which will account for 40 per cent of the marks.

David Blunkett, Labour's education spokesman, said it was vital that the new qualifications were seen as high-quality.

Don Foster, the Liberal Democrats' education spokesman, said: ``There must be some concern that the recent criticism of the new GNVQs appears not to have been taken on board. It is vital that they are got right first time, given the crucial role they will play in achieving parity of esteem between academic and vocational qualifications.''

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