Nothing seems more remote at the start of a new autumn term than the end of the previous one. September is a time for beginnings, not reminiscences. But for me the end of the summer term encapsulated tensions that look set to continue during the coming year.

Late July was full of press reports about English children’s comparative failure in mathematics. By then, concern that there were genuine problems was quickly overlaid by irritation that the story was being re-cycled on some kind of monthly treadmill without reference to how the problems were being tackled.

On the same day I had been reading these reports I spoke to a relative whose 11-year-old had just finished his last day at primary school. It had been an emotional occasion. He had been happy at the school and was sad, after six years, to be leaving. His parents had been delighted with how ably the school had taught him. His teacher, I was told, had been visibly moved to be parted from a group of children (and parents) whose lives she could feel proud to have shaped.

The two images sat uneasily together. How could one reconcile the need to celebrate the many positive things about schools with the need to create a greater sense of urgency about the problems and issues, some quite fundamental, queuing up for attention? Looking back over the year, it was clear that collectively we had not done it very well in 1995-96, and must do better next year.

What we need in education is the application of Aristotle’s “golden mean”: a balance between a sense of our own value - something which all individuals and communities need, in order to keep going - and the stimulus to improvement that comes from a sharp awareness of our deficiencies.

Too much praise can produce the cosy consensus we have often had, for example, about “best primary practice” - practice which has sometimes been far from “best”. Too much criticism can lead to low self-esteem and a consequent defensiveness in response to any attempt to raise fundamental issues: the depressing response that schools are doing a very good job, thank you very much, and that therefore there is nothing to talk about. As we begin a new school year, we need to try harder to achieve a sense of balance between the positive and negative aspects of our education system.

First, the positive. In a society which has lost faith in many of its public figures, we need to keep on reminding ourselves of the respect with which children and their parents regard teachers. In poll after poll, teachers top the list of groups of people whose judgment is trusted. At a time of mounting concern about civic disintegration and the weakening of traditional moral values, the role of schools in holding up a model of an ethical community should not be underestimated. Schools by and large are moral places. Indeed, as the Chief Rabbi has said, they often seem like “beacons of civilisation” amid a darkening world.

We also need to publicise the many improvements made by schools and colleges in recent years. When I compare what schools were like at the beginning of my career in education in the late 1960s I can identify much we have lost, but also much we have gained.

Compare provision for lower attaining pupils then and now, compare the breadth and balance of curricula; compare attitudes towards bullying; compare expectations of girls; compare how schools monitor their own performance; compare the percentages of young people achieving basic qualifications; compare the proportion of the workforce with qualifications up to and including national vocational qualification level 4 (where the UK now ranks third in the world).

Qualifications are a case in point. We are now used to the annual search for reasons why an improvement in A-level results cannot be the result of harder work on the part of students and teachers. I share some people’s unhappiness about some of the changes to A-level and GCSEO-level syllabuses over the past 20 years. There have been shifts in emphasis about which we may have legitimately different views. But evidence of diminished demand is rarely conclusive, and sometimes offset by counter-evidence of increased demand. What one rarely hears about are all the reasons why results might be genuinely better: higher expectations of girls; a big expansion of social classes 1 and 2; the impact of greater school autonomy, open enrolment and performance tables; and more effort on the part of students and teachers.

There is undoubtedly an English disease which leads some people, especially intellectuals, to belittle our achievements. Schools are suffering from the side-effects of a general weakening of a proper sense of pride in our culture, history and distinctiveness. When there is a collective lack of identity and self-esteem it is not surprising that, Cassandra-like, we always see and fear the worst.

But the other side of the “golden mean” is an awareness of our deficiencies and of the fundamental issues yet to be grappled with. Here I wish to single out four.

* First, the huge variation in attainment across schools of similar type. Despite improvements, far too many children reach key ages unable to achieve what might reasonably be demanded of them. The figure of 20 per cent of the cohort unable to achieve a G at GCSE in English and maths, the expected attainment level of a 10 to l1-year-old, is terrifying. The way forward is at school level, through inspired leadership, high expectations and a willingness to re-examine teaching methods. Many schools have already pointed the way.

* Second, at national level, the need for a new awareness that education is a field with few instant results, and few easy solutions, and which in matters of teaching and learning benefits from a unifying strategic direction as independent as possible of party politics.

* Third, the importance of engaging more with the ideas, values and attitudes that underlie everything we do. One of the fascinating things about education is the way our choices are so often determined by our views and assumptions about human nature, our fundamental ends and purposes, and the society we wish to live in. We will not sort out, for example, the nature of the primary curriculum, the place of moral education or the purpose of arts education unless we engage with, and are less embarrassed by, these deeper issues.

* Finally, the need for those in education to go on the offensive and challenge society. Schools suffer as a result of the pervasive sense that society has got worse, and that therefore they must in part be to blame. Society is certainly often far from supportive of what schools are trying to achieve. The preoccupation with rights and wants, and with material goods, together with the impact of mass media and of a synthetic youth culture, and the poor example of some public figures and some parents, undermine schools’ best efforts.

There is also perhaps in egalitarian societies a danger of sinking to the lowest common denominator, especially in moral and cultural matters and in matters of the mind that are “difficult”. The education system should challenge any such tendency through an uncompromising pursuit of excellence and rigour - for all students at all levels.

We need to tell the world, much more loudly, that this is what we are already doing. And where we are not doing it we need to be frank about our failings and ruthless in our analysis of what caused them. That may be quite a tall order for the new school year, but new years need to begin with high hopes.

Dr Nick Tate is chief executive of the School Curriculum and Assessment Authority.