John McLaren, an economist and former adviser to the late Donald Dewar, has cited evidence about exam results at S4 and participation rates in higher education to suggest that Scotland is failing to make the progress evident in England. Lindsay Paterson of Edinburgh University, in an address to the Institute for Public Policy Research, draws a similar conclusion, stating that "devolution has had almost no impact on opportunity through education".
However, it is the third source of criticism that I want to focus on. This was a report by Reform Scotland, an organisation which describes itself as "an independent, non-party think tank". It concentrated on the costs of state education and concluded that, despite a substantially increased budget over the last 10 years - evident, for example, in improved per capita expenditure for both primary and secondary pupils - the educational system is failing to produce value for money in the shape of improved results. Among its recommendations are greater powers for parents and greater autonomy for schools.
Reform Scotland's website states "our vision is of a free, dynamic and competitive economy in Scotland with educational standards that compare with the best in the world". It has similar aspirations for health, transport, employment and law enforcement. Economic success and continuous growth is seen as fundamental to the provision of effective public services.
But is the organisation really "independent"? Director Geoff Mawdsley has a background in public relations and political strategy, and for eight years was the chief policy adviser to the leader of the Scottish Conservative Party.
A study of the people serving on Reform Scotland's advisory board and board of management reveals a very striking pattern: nearly all have strong business links, with the financial services sector particularly well represented. Given the recent history of that sector, it might have been thought that a degree of reticence about the alleged failings of public services would have been appropriate. But judging by the actions of Sir Fred Goodwin, arrogance seems endemic within the culture of banks, insurance companies and investment trusts.
However, even if this should cause us to treat Reform Scotland's report with scepticism, there is one respect in which we should be grateful for its entry into debates about educational policy. For too long, understanding of the economics of Scottish education, even among those who have substantial professional responsibility for the allocation of funds, has been sadly deficient.
Educational researchers have been slow to see this as an area ripe for development. If we are serious about trying to ensure that educational policy is better informed by reliable evidence, the level of understanding of the costs and benefits of investing resources needs to be greatly enhanced. Of course, cost should not be the only consideration in determining educational priorities but, in the present financial plight, it would be reckless to rely on well-intentioned amateurism.
A good start would be the establishment of a Centre for the Study of the Economics of Education in one of our universities. Such a centre would have to be genuinely independent, both of government and of the various pressure groups which try to capture the policy agenda.
Walter Humes is research professor in education at the University of the West of Scotland.