Most school sixth forms are popular with students, who learn well in them, according to a new study from the Office for Standards in Education. However, about half of schools are insufficiently aware of sixth form costs and more should make the effort to find out how effective they are.

The study suggests that schools need a clearer idea of sixth-form income and expenditure. They should also make more use of value-added analysis, both to set targets for individual students and as a basis for departmental review.

The inspectors also found that fewer than one in five schools had distinct aims and written policies for their sixth form and that few had a clear rationale for defining what they offered other than exam courses. Indeed, just under one in 10 sixth forms offered nothing but exam courses.

The study, Effective Sixth Forms, is based on an evaluation of 92 school sixth forms in 1993-94 followed by extended visits to a further 18, many selected on the basis of favourable OFSTED reports, in 1994-95.

It suggests that 80 students are the minimum needed for a sixth form offering A-levels and a reasonable extra studies programme within the funding allocated (usually Pounds 2,200-2,400 per student). But an effective sixth form offering 12 A-levels, two intermediate general national vocational qualifications and one advanced GNVQ would need 125 students. Out of the 18 schools in the second set of visits, two-thirds were judged by inspectors to be cost-effective. These had between 100 and 335 students.

Four schools singled out for praise include a large 14-19 community college in Yorkshire and a small upper school in Suffolk with 118 sixth-formers forming part of a consortium with two other schools.

The inspectors considered sixth forms “effective” where: * the curriculum matched students’ skills and aspirations, taking into account complementary provision elsewhere;

* students were given suitable guidance;

* a high proportion completed their courses and passed the exams and the courses built well on their previous achievements ;

* extra studies and activities were of clear benefit.

Sixth forms were, in addition, judged “cost-effective”, if the share of resources they used matched the proportion the school received for sixth-form students - although, as the report points out, this begs the question of whether they are given the right amount in the first place.

Schools have only recently become strongly aware of cost-effectiveness, say the inspectors. Few schools visited in 1993 were sure how much their post-16 places cost; those visited in 1994 were much more aware of expense, although few knew how to analyse anything other than staffing costs.

Students were positive about the quality of their sixth forms. They valued the security of an orderly community with which they had become familiar over a number of years and the co-operative relationships they had developed with teachers. They liked the freedom to choose subjects and organise their work, within a regime which set high standards.

Schools regarded the sixth form as essential to recruiting and keeping good staff and maintaining their reputation and ethos .

The lessons inspectors saw in their second round of visits reflected the students’ confidence. Quality of learning was judged good in about two-thirds of cases. This reflects the findings from a much larger sample on the national OFSTED database of schools, where standards were satisfactory or better in 93 per cent of A-level lessons and nearly 90 per cent of GNVQ lessons.

The study shows once again the failure of AS-levels to broaden the sixth-form curriculum. While they were offered in at least one subject (usually maths) in some 60 per cent of schools, few offered more than two subjects and take-up remained low. Intermediate GNVQs have largely replaced GCSE re-sits in sixth forms, the study also shows.

The report describes some ways of achieving cost-effectiveness .

A school offering only A-levels would be able to provide 12 A-levels with a sixth form of 80 students. This would allow five hours of taught timetabled time for each A-level subject, co-teaching of the two years in two subjects (art and technology), AS courses taught only as part of A-level courses and three hours left over for extra studies and guidance.

To extend this basic curriculum would mean either adding more students or making cuts in timetabled time. Adding two intermediate GNVQs in business and health and social care, for instance, would require an extra 36 hours of timetabled time and could be viable with 100 students. But a sixth form running only those two GNVQs and no A-levels could break even with only 22 students.

Advanced GNVQs need more teaching time: an extra 36 hours of curriculum time to teach a GNVQ in business, for instance. Adding that to the model would bring the total of students required to 125.

But the report points out how teaching time can be saved. For example, some minority subjects, like further maths and modern languages, can use more self-study materials: reducing the teaching time by a third would allow an additional A-level to run.