Seona Reid, director at the Scottish Arts Council, told delegates: "You teachers are burdened with a curriculum that is overstuffed. It's difficult to see how you could get more into it."
She was responding to a complaint from Gaye Linklater, head of Hermitage Park primary in Edinburgh, who complained that the expressive arts were being "sidelined" in the 5-14 curriculum because of target-setting. Ms Linklater also criticised the 5-14 levels in art and music as "counter-productive".
The exchanges brought to life the conference on "Children, participation and the arts," organised by the Scottish Arts Council and Children in Scotland, which was held at the Edinburgh International Conference Centre.
Brian McGeoch, South Lanarkshire's arts development officer, made a spirited defence of the curriculum which he said gave children access to the arts that they had not experienced before, through visits to theatres, museums and galleries.
"What the 5-14 curriculum doesn't ask us to do is say how good a particular child is at art," Mr McGeoch said. "You cannot assess that. It is providing a programme for children to experience art."
But Mr McGeoch's was a lone voice and the general mood was one of discontent over the place of the expressive arts within the 5-14 curriculum.
The strength of feeling was particularly striking as very few of the papers from Scotland directly tackled curriculum matters. One exception, a United States import, was the community-based Lakeview Education and Arts Partnership in Chicago. It obtained funds by proving that it can raise pupil achievement, Jacqueline Murphy of the Chicago Teachers Centre told the conference.
For seven years 70 teachers have worked with 20 artists and 1,800 pupils from one high school and three elementary schools. The project developed 70 units integrating, say, dance and maths or visual arts and science. These are co-taught by teachers and artists.
"They create something totally new in terms of creating a curriculum," Professor Murphy said. "We have to document, assess and write the curriculum."
Another conference theme was whether the arts should be seen as "a subject or a mechanism", as Magnus Linklater, SAC chairman, put it.
Sian Fiddimore of the Wester Hailes Arts for Leisure and Education in Edinburgh spoke approvingly of "the arts being used to achieve curriculum needs".
But one music teacher complained: "Excellence in the arts is not valued unless in terms of self-esteem and all the other offshoots of the arts. But what about producing excellence?
"Headteachers are keen to give you money in terms of attainment or helping boys. If I say I want to create excellent oboe players, there's no money."
Many speakers called for a flexible approach to introducing arts. Tony Reekie, director of the Scottish International Children's Festival, said:
"We must work for and with children, not see art as something done to them. We should explore themes which engage children rather than be issue-based."
The conference was opened by Rhona Brankin, deputy minister for culture and sport. A former teacher, Ms Brankin said: "Creating art for children has always been threatened by two phantom menaces: condescension and sermonising.
"It therefore requires exceptional skill and sensitivity to create work that simultaneously relates to children's views of the world and seeks to expand their horizons."
Ms Brankin's twin responsibilities may have prompted Ian Sutton, an arts development officer from Bexley, Kent to observe that sport had gained a more popular foothold among children, than the arts.
He suggested this was because of the Sports Council's emphasised participation, whereas the Arts Council's more passive approach viewed arts as a role for the professionals while the rest made up the audience.
Ms Reid, the SAC's outgoing director, accepted the criticism as "fair".