The Commission for School Reform said the implementation guidance around CfE ran to 20,000 pages and placed too heavy a burden on teachers.
In June, a report into CfE from the Organisation for Economic Co-operation and Development (OECD) said CfE had suffered from failures of implementation.
Chaired by Dr Keir Bloomer, one of the architects of CfE, the Commission on School Reform has published a paper examining the OECD report.
Dr Bloomer’s group stressed the importance of the acquisition of knowledge as well as skills in education.
It called on the Government to “radically simplify” the implementation of CfE.
Carole Ford, a former headteacher and a member of the Commission on School Reform, said: “The OECD report is lengthy but its central point is clear – that CfE is conceptually worthy but poorly implemented.
“That is primarily down to the ridiculous amount of national implementation guidance, which runs to 20,000 pages, and which is overburdening teachers.
“The best way for the Government to proceed on this guidance is to get rid of it, and to let schools and teachers implement the framework of CfE at their own discretion.
“The other major change which is required, and on which the OECD also comments, is the role of knowledge.
“It’s all very well to place a central role for skills in the curriculum, but unless the acquisition of skills sits alongside the acquisition of knowledge, they will have very little value.”
A Scottish Government spokesman said: “The OECD, in their independent report, have been crystal clear – Curriculum for Excellence (CfE) is the right approach for Scotland and is viewed internationally as an inspiring example of curriculum practice.
“Throughout the pandemic it delivered credible results for our children and young people in the face of exceptional circumstances.
“The breadth of learning delivered by CfE – which helps equip pupils with the knowledge, skills and attributes needed for life in the 21st century – was reflected in the recent PISA global competence assessment, where only two countries achieved a higher average score than Scotland.”