In an article for Create - a journal of perspectives on the value of arts and culture published by the Arts Council - Sir Anthony Seldon, master of Wellington College, writes:

Do we truly understand the purpose of education? Do we really think that going to school is only about achieving good exam results? Ministers - and the education establishment - can give the impression that exam results are the Holy Grail, the only way to judge the accomplishment of schools and students.

Of course, we recognise the vital role exam results play in evaluating the effectiveness of funds and policy. There should be measures of accountability and goals to aspire to. But in pushing education to new heights we must not lose its breadth.

For years, many thoughtful and brave voices have been saying that a focus on exam passes misunderstands the mission of education. Perhaps this is because those who decide education policy have rarely worked in schools, and lack first-hand understanding of the extraordinary complexity of education.

In point of fact, I would contend that if you really want to improve exam results, you should focus less on the outcome and more on the process and environment in which children learn. This is not softness, not excessive liberality; it is common sense.

When the results achieved by independent schools are analysed, it is often without considering the role that a rounded education plays in this success - and particularly the role of the arts. It is also this unequal provision of culture that gives the alumni of independent schools a substantial advantage throughout life.

Similarly, the commentariat talk about stagnant social mobility but rarely look at why it is occurring - and I would contend that unequal access to an education in the arts is one important reason. In England, this is mostly limited to those already economically privileged. This is an unjust waste of national talent.

Other nations are aware of the difference the arts can make in education. Take the case of the Turnaround Arts project in the United States, in which failing public-sector schools, with huge social disadvantages, are being dramatically improved through an immersive arts programme.

Recently we have heard much about the extraordinary improvements in London secondary schools over the last 10 years, as gauged by GCSE results and Ofsted ratings. These are important, but surely they don’t go far enough as measures of success; they indicate the necessary, not the sufficient conditions for a good education.

You can teach students to do well in exams without teaching them in any depth. Students can achieve top grades but know little and understand less about the world and their role in it, or how to be happy.

A good education should be a preparation for life. It requires the development of the whole child, not merely their intellect. It necessitates students becoming intrinsic learners with self-discipline and a genuine thirst for knowledge, rather than being goaded or corralled, which is what students may become with a single-minded focus on exam results.

Research shows that self-discipline is a better predictor of success in life than IQ tests - and it has further shown that good character and resilience can be taught at schools, with lifelong benefits. Work at the University of Birmingham Jubilee Centre for Character and Values shows that an undue emphasis on exam passes robs young people of the broad education that schools should be providing.

The argument has been put succinctly by the distinguished educationalist Howard Gardner, Hobbs Professor of Cognition and Education at Harvard. He says the question that schools should ask is ‘not, how intelligent is this child, but rather, how is this child intelligent?’

I drew inspiration from Gardner’s writing on multiple forms of intelligence - including cultural intelligence - when I became head of Wellington College in 2006. We redesigned the entire curriculum and co-curricular life of the school around eight separate ‘aptitudes’: artistic, physical, logical, linguistic, personal, social, moral and spiritual. I believe all schools should nurture these different facets, which otherwise might remain dormant within each child. The arts are an intrinsic part of this approach.

Wellington College is not unusual among independent schools. Two thirds of pupils learn a musical instrument (I would like that figure to be 100 per cent); all take part in singing competitions and are given opportunities to act and present on stage. All are offered the chance to draw and paint, are encouraged to write creatively and have the opportunity to dance. The school is alive with performances, the corridors and walls are a permanent art gallery, and music is heard everywhere.

Why should students at independent schools enjoy such a rich education in the arts, whereas in most state schools - where it could be so effective and is most needed - it is a hit-and-miss business?

Some of those who show an early gift at state schools might receive encouragement, but the mass is often ignored, as if their creative potential is of little value. True, state schools have fewer resources in general than independent schools but some manage to offer music, drama, dance and creative writing, as well as wonderful opportunities through their art departments. This should be normal for all schools, for denying an arts education to the young will limit their chances of learning self-expression and of achieving profound personal fulfilment. It’s about their potential - and their lifelong happiness.

I would argue that every single child in a state school should have access to the five forms of the arts to the same degree as pupils at independent schools.

Melody and rhythm lie deep in the soul of every human being. Every pupil should be taught a classical instrument. What other lesson can we draw from the wonderful El Sistema story than the powerful cultural and social impact on all young people of music?

The state should fund universal musical education. There are encouraging signs that the government is beginning to recognise this, and I welcome the additional money that has recently been made available to music hubs. But we need more - both financially and in terms of leadership, to get music and the arts up the educational agenda.

Every child should experience the thrill of playing in a musical ensemble. It will be one of the most profound experiences in their lives; they will learn about self-discipline, teamwork and trust. All young people should be taught to sing and have the chance to perform in concert. Schools should reverberate with music in their corridors and lunch halls.

Drama is equally vital to emotional and intellectual development. Before self-consciousness sets in, children naturally want to act and perform. Acting gives young people confidence and augments their ability to express themselves in public - a vital career skill.

Visual art generally fares the best of the five artforms in schools. But even visual art’s importance is not properly understood, and not every child learns to draw and paint from an early age. Art is the most universal language of all and the earlier it is taught, the better. Throughout their years of formal education, students should come to understand the history of art over the last 2,000 years, from the classical world to Tracey Emin. Doing so will give them the means to enjoy and understand art and architecture - the environment they live in - throughout their lives.

Creative writing plays second fiddle to literary appreciation in most schools. Yet learning how to express ourselves, whether in poetry, prose or drama, provides a crucial psychological outlet, and an invaluable professional skill. Learning how to write enhances the value and pleasure to be derived from reading.

Dance, the fifth art form, has fared least well in schools, despite its growing popularity amongst the young. The rhythms of dance lie deep in the human psyche and learning to understand dance should be important for boys as well as girls. Again, it is an artform that achieves personal expression and liberty through great discipline - and it’s healthy exercise.

Offering these opportunities to the young represents a long-term investment in their talent and happiness. They will develop interests that blossom, giving them skills of self-confidence, presentation and articulation. These will improve their professional progress, and will enrich their personal lives immeasurably.

A true arts-based education for all should not be a dream. It should be a priority. It will make schools more civilized, children wiser and more reflective, academic learning more productive and harmonious, and it will turn out young men and women who will be better citizens and happier humans. It will break down the barriers of chance and privilege and make our society more genuinely democratic.

Last month, I walked past the Grey Coat Hospital Church of England Comprehensive School for Girls in Westminster and saw girls streaming out of the front door carrying violin and cello cases. When all state schools are like this, we will be achieving real equality of opportunity.

Create - a journal of perspectives on the value of arts and culture will be published by the Arts Council on 18 November

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