More recently, as higher education has expanded, the grounds of the attack have changed. It is suggested that A-levels are too narrow and create an artificial academic-vocational divide. Critics advocate some grouped or overarching award which, ironically, is what A-levels replaced.
But a cool look at the various charges suggests that they may have less to do with A-levels as such than the role of qualifications post-16, and that in most cases A-levels are a better bet than the alternatives.
Take differentiation, for example, providing the information that admission tutors and employers often require. If A-levels were scrapped, this would still be needed. Any opprobrium attached to A-levels in this respect would pass to their successor. But while A-levels are good at identifying academic ability (suggestions to the contrary are based on misinterpretations of correlation statistics)a diffuse grouped award is likely to be less so.
Neither are A-levels necessarily narrow. They allow students to specialise or pursue breadth across a range of combinations according to their abilities and interests. Behind the arguments for a grouped award is the belief that breadth is so important that it should be compulsory. But what, in fact, are the advantages of studying, say, chemistry, economics, German and history imposed by a particular framework rather than some freely chosen combination?
The Baccalaureate idea involves unitising all existing qualifications, in the hope and expectation that A-levels will dissolve away. The experience of New Zealand, however, has been that fragmentation of this kind both increases bureaucracy and reduces coherence.
The qualifications structure beyond GCSE has to be flexible and based on choice. But it is important that this choice is exercised over meaningful chunks that bear some direct relation to the opportunities ahead. A-levels would seem to better serve this purpose than an amorphous grouped award made up of numerous bits and pieces.
But the main charge against A-levels is that they reinforce an arbitrary academic-vocational divide. It is claimed that an overarching award would promote "parity of esteem". But the value of a qualification is related to what you can do with it. Academic awards are not automatically accorded higher status than vocational ones. Medicine and law - vocational degrees - are more prestigious than their academic counterparts.
Advanced qualifications in physics and mathematics carry higher status than those in leisure and tourism because they open more doors. Any difference in prestige is less to do with A-levels themselves than where they lead.
An overarching certificate might fudge the issue, but new status differences would soon emerge, as in France where there is a distinct pecking order for general, technological and professional Bacs.
A-levels are, in fact, more in tune with the organising principles of post-school studies. Sir Ron Dearing, in his report on qualifications for 16 to 19-year-olds distinguished three: the academic, applied and occupational. The "academic" is centred on ways of making sense of the world, the "applied" on particular classes of practical activity and the "occupational" on specific training.
Representing these modes as different qualifications conveys more than running them together under one label. A range of awards does not imply tramlines. Thenew AS examination has already paved the wayfor flexible combinations of the academic and applied. An overarching certificate would be merely superfluous.
The Government has so far been commendably cautious in resisting the pressure. It is aware that the general public likes A-levels because they know where they are with them. The Government also recognises that employers are increasingly turning to A-levels instead of relying on degree classifications that they regard as somewhat suspect.
No doubt the siren voices for an overarching certificate will continue. But before doing away with A-levels the Government will need to be much more confident than it can be now that the balance of advantage lies elsewhere.
* Alan Smithers is professor of policy research and director of the Centre for Education and Employment Research at Brunel University and Sydney Jones professor of education-elect at the University of Liverpool