SECONDARY headteachers have given a damning insight into the troubled roll-out of Scotland's school curriculum and exams.

A raft of concerns have been raised by schools as part of written evidence to the Scottish Parliament's education committee, which is looking at the introduction of the Curriculum for Excellence (CfE).

The evidence is unusual because individual headteachers from the state sector rarely give their views because they are employees of their local authority.

Subjects covered include the heavy workload on teachers, poor marking of exam scripts and lack of support from the Scottish Qualifications Authority (SQA).

In an extremely frank critique Derrick Hannan, headteacher of Braidhurst High School, in Motherwell, described the move away from an external exam in some qualifications as a "total disaster".

He said: "It is divisive and is causing a breakdown of the whole basis of comprehensive education. In my school more than half the students never sit any examinations whilst others sit a few and a tiny number sit a normal examination diet.

"The net result is the creation of groups of pupils who feel a total lack of any sense of self-worth. We have created a junior and senior secondary system based within the one building."

David Dempster, headteacher of Boroughmuir High School, in Edinburgh, also attacked the levels of SQA assessment and warned of current problems delivering new Highers this summer and Advanced Highers next year.

He said: "There is no doubt the demands of assessment that have shifted to teachers is wholly disproportionate. On paper these demands may seem reasonable for a single course, but when pupils are doing a suite of courses it is wholly unmanageable."

Melvyn Roffe, principal of George Watson's College, a private school in Edinburgh, said the overwhelming message emerging from staff was of too much assessment - again with concerns this was being replicated at Higher and Advanced Higher qualifications.

He said: "A transition to alternative methods of assessment requires a huge change of assessment culture and behaviours which is unlikely to occur whilst

we are in a climate of curriculum change and of general uncertainty amongst staff in understanding standards.

"The concern arises because there has been a disparity between the SQA operations team and subject specialists in the guidance, key messages and support that they have provided. This confusion and uncertainty leads to staff not trusting the process."

David Nicholls, headteacher of Gleniffer High School, in Paisley, said preparation over the past five years had lacked "clarity, direction, leadership and planned or structured support".

He said: "There has been no long-term planning and no acknowledgment of the work that teachers have had to put in to make all of the courses currently running in schools work."

Colin Stewart, headteacher of the private Hamilton Grammar School, in Hamilton, said workload had been cited almost unanimously by staff.

He added: "There is a perceived lack of support and exemplification from SQA, particularly vexing when staff are trying to get a sense of the standards on their first year of delivering the new courses. I believe that as a country which wants and needs to have a world class education system we could have done better in this respect."

John Rutter, headteacher of Inverness High School, added: "Concerns have been raised in Highland about the robustness of the marking process with, in some instances, up to 50 per cent of appeals being successful.

"This brings into question the rigour of some marking processes and needs to be sorted out so that all pupils stand an equal and fair chance of success."