Keir Bloomer, vice-president of the Association of Directors of Education, cited a whole series of challenges - from computer-based learning, moves towards a skills-based curriculum, home education and tutoring.
Mr Bloomer pointed to the opening of Britain's first high-tech learning centre in Hemel Hempstead. Aimed at the training markets, he suggested its technology could potentially deliver most of the secondary curriculum.
"I am not arguing that schools are becoming irrelevant," Mr Bloomer told last week's education conference in Edinburgh, "but rather that, if they are to remain relevant, they must reconsider what is their core business."
He suggested that core should be "a complex amalgam of cognitive, personal and social objectives which a school committed to the total welfare of the young person and his or her family may be uniquely placed to deliver. Education is a personally transforming experience and it needs socially responsible agencies to provide it."
But even the social experiences which may be one of the chief justifications for schools can be negative, Mr Bloomer argued. "Some families see schools as places where their children are bullied, where drugs are traded and where boys particularly are subject to anti-achievement peer group pressure."
The response in the United States has been the rapid expansion of home education, supported by a network which now involves three million children.
Mr Bloomer called for a move away from "an obsession with content" in the formal curriculum towards developing key transferable skills such as learning to learn, promoting self-confidence and helping pupils relate to others.
The Clackmannanshire director continued: "I am convinced that the unrelenting pressure on young people to submit to ever-increasing periods of content-based education, thus protracting their economic dependency, is a key factor in growing youth disaffection.
"We have sold the instrumental value of education. Everyone believes you need pieces of paper to progress. But we have not sold the intrinsic worth of the product. Young people have yet to be convinced that secondary schooling is a valuable experience in itself.
"This is not the fault of teachers but of misconceived curricular theories."
Despite Government rhetoric about encouraging enterprise and citizenship, Mr Bloomer said, prescriptive curricular guidelines meant such things were not at the heart of schooling.
"Indeed, it could be argued that by placing young people in an environment where they have few unconstrained choices, no economic opportunities, little control even over their own learning, schools actually discourage enterprise and fail to create the circumstances from which active community involvement might emerge."
He said the relevance of schools might be helped if they were judged against a wider background than simply "hard-edged measures" such as exam results, or "fatuous proxies" such as the number of weeks it takes to process a record of needs. Important as measuring performance was, it could often come to be seen as an end in itself and lead to compliance with a centralist agenda.
Despite his reservations, however, Mr Bloomer said he had never felt so optimistic after 30 years in education. "I believe we are beginning to get it right. We are not just asking some of the right questions but offering at least a few of the right answers."