Keir Bloomer, vice-chairman of Learning and Teaching Scotland, and Mike Baughan, its outgoing chief executive, said that the time had come to think radically about the curriculum, They were supported in this by Wendy Alexander, the former lifelong learning minister, who hoped that the forthcoming curricular review would not just be about the balance between different subjects.
"Are we just playing at this, or are we serious?" Ms Alexander asked the witnesses.
As reported in last week's TES Scotland, Mr Bloomer, a member of the review group, sought to reassure her that the review would confine itself to setting out the principles and philosophy that should lie behind the curriculum.
Previous attempts at reform, particularly that by the influential Munn committee 30 years ago, had done the same "but they had then felt constrained to produce a model".
Mr Bloomer added: "They started out by appearing to open up the debate and then produced a blueprint which closed it down."
Mr Baughan said that previous curricular designs had attempted to introduce flexibility, but curriculum managers in schools had latched on to the suggested models in a prescriptive way - which he described as "depressing".
Mr Bloomer said the experience of school subjects in decline - such as modern languages and science - had shown that "coercion is naive and has been shown to be naive".
He said that mistaken thinking had been responsible for the perilous state of modern languages in schools. "The result is that 95 per cent of pupils drop modern languages at the first opportunity with a level of attainment indistinguishable from what would have been the case if they had never studied languages in the first place."
Mr Bloomer said the arguments for studying modern languages in schools - the advent of globalisation and Britain's membership of the EU - "are little better than slogans".
The motivation in an English-speaking country to learn another language was minimal. French predominated "only because we have a lot of French teachers".
Mr Bloomer also pointed to the decline in science which he described as being stuck in "the history of science, if not the archaeology of science".
It was still taught as physics and chemistry "with biology as an also-ran". These were not areas of science "in which knowledge is conspicuously advancing".
Mr Bloomer noted that the fastest-growing subject in England at GCSE is religious studies , which was "not the outcome of a rapid upsurge in faith, but because it is a subject area in which young people can do what a great many of them want to do: talk about big questions and issues.
"Science has the opportunity to offer that as well, but so far we haven't taken up the opportunity."
Cramming content and knowledge into school subjects had been responsible for turning pupils off science and modern languages, Mr Baughan added.
Learning would only take off where pupils were involved in discussion about what they were going to learn and why, Mr Bloomer said.