A key initiative to boost pupil attainment could fail to work properly because of unrealistic expectations of what it can achieve, an expert has warned.
Schools and local authorities must not look at the School Effectiveness Framework (SEF) as the "be-all and end-all" when it comes to improving results and well-being, according to Michael Fullan, a leading authority on school improvement and an adviser to the Canadian government.
Educators must also not be afraid to publish data on results, Professor Fullan said.
The SEF is the Assembly government's key policy for reform, aiming to increase pupil achievement and wellbeing by improving the quality of teaching and leadership in Welsh schools and local authorities.
Professor Fullan, from the Ontario Institute for Studies in Education at the University of Toronto, said: "The danger is that SEF is seen as being built to carry too much weight. That may be too ambitious. For us (in Canada) it's only one tool - it's not the be-all and end-all."
Professor Fullan also told TES Cymru that the policy might be held back by a "fear" of league tables in Wales. "I think that fear has caused educators to be too cautious," he said. "I feel there has to be more risk- taking because you can't get anywhere unless you are more transparent about results, data and practices."
Visiting Wales as part of an international tour, Professor Fullan discussed the SEF with headteachers and other practitioners at a major conference in Swansea.
Alma Harris, professor of education leadership at the University of London, told delegates that there was a "really small window of opportunity" for the SEF to make a difference to education in Wales.
"If we are really serious about closing the gap and raising the bar we need to start thinking, acting and believing differently," she said.
"We are punching well below our weight. I know we can do a lot better than England; we should be doing a lot better than England. I believe we can out-perform England and many other countries if we work together."
Chris Tweedale, director of the Assembly government's Children, Young People and School Effectiveness Group, had earlier told delegates that Wales should stop comparing itself with England.
Mr Tweedale was head of five secondaries in England and worked at the then Department for Children, Schools and Families before coming to Wales last year.
He said: "We need to be comparing ourselves against the best in the world. We have got into the mindset of comparing ourselves with England, but we are a very different country with very different policies."
He went on to say that the SEF could help Wales have a world-class education system.
Leighton Andrews, the education minister, told the conference it was time to move from the framework to action to make an impact at school level.
He said: "It's the right of each and every young person to have high- quality teaching and learning. It's about developing a culture of leadership and best practice for all involved in the education system at all levels.
"There are many challenges ahead of us, and we face challenging financial settlements, but I'm sure we can make a significant difference working together collaboratively."
The Assembly government has launched its long-awaited SEF website, where schools and local authorities can learn more about the framework.
- It is Wales's key policy for education reform.
- The initiative aims to improve attainment and well-being of all children and young people and reduce variations between schools and individual classrooms.
- All other education policies will be aligned to it, as well as Estyn's new inspection framework.
- It is driven by "tri-level reform" - schools, councils and the Assembly government working together.
- It will focus on improving teaching and leadership and sharing best practice.
- The initiative will be put into practice in September 2010.