Estyn says too many empty places in schools in Wales
The number of empty school places needs to be cut to save money and improve standards, the Schools Inspectorate for Wales has said.
Estyn says councils are reluctant to take difficult decisions and need to do more to re-organise or close schools with surplus places.
There were nearly 100,000 surplus places in Wales last year.
But governors and teachers leaders say the issue is more complex and needs more consideration.
Meanwhile, the Welsh government has welcomed the report and said decisive action was needed.
Estyn says councils "have been slow to identify and complete projects which could lead to significant savings".
Every local authority has to ensure it has enough school places for its pupils.
End Quote Alec Clark, Association of Teachers and Lecturers in Wales
It is not a simple thing to say we have spare places. This needs to be looked at in far more detail.”
Alec Clark, president of the Association of Teachers and Lecturers in Wales, said it was carte blanche to consider schools' future purely on the number of places.
"This would have a huge impact on rural schools where often it's a case there are less than a dozen pupils and perhaps schools are kept open with very few pupils knowing that there will be a blip in uptake in several years' time," he told BBC Radio Wales.
"It is not a simple thing to say we have spare places. This needs to be looked at in far more detail."
The Estyn report acknowledges that balancing the numbers to avoid surplus places can be difficult, but says little progress has been made since 1996, when guidance was published on tackling the problem.'Impact on the community'
The inspectorate found that in 2011 there were more surplus places than 2006, and no local authority had achieved the Welsh government's recommended target of no more than 10% surplus places across primary and secondary schools.
The report lays some of the blame with the local authorities it says are "reluctant" to make difficult decisions about school closures and reorganisation.
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It argues these are the most effective ways of redirecting money into raising education standards.
Among Estyn's other recommendations, it believes a standard method of calculating the cost of surplus places would help people understand the need for change.
Estyn chief inspector, Ann Keane, said: "This is a difficult task as, currently, we are seeing an increase in the number of primary pupils but a decrease in pupil numbers in secondary schools.
"However, despite the removal of some surplus places, local authorities have been slow to identify and complete projects which could lead to significant savings."'Decisive action'
She said the Welsh government and local authorities needed to "assess the financial and education impact of previous school rationalisation schemes as well as the continued impact of high levels of surplus places on all aspects of funding for school improvement".
The Welsh government said it welcomed the report, commissioned by Education Minister Leighton Andrews.
A spokesperson said it would respond to the recommendations, adding: "We recognise not all places are surplus to requirements but local authorities must consider whether their supply of places and, more particularly, the number of schools maintained in specific locations is appropriate or excessive.
End Quote Steve Lamb Estyn report author
One of my concerns in writing the report was that we simply do not know enough about the surplus place situation in Wales”
"Where schools can be organised more efficiently and effectively, local authorities need to take decisive action.
"They must also plan carefully, as in some areas the number of young pupils in the system has increased in recent years."
Teifion Rees, chair of governors at Cwrt Sart Community Comprehensive in Briton Ferry, who has been campaigning to save his school from closure, says there should not be a blanket rule for all schools.
He said before such decisions are taken it was "absolutely vital" that local authorities look at how schools were performing and "consider the impact on the local community".
Olivia Elliot, a founding member of an action group established to save Bron y Foel primary school in Caernarfon, said parents would not allow a school to close unless it was justified.
"Is it going to cost the council more money to transport these children to the different schools? These are the sorts of questions we as parents want answering before we sit back and 'yes, just close our school'," she said.
Estyn report author Steve Lamb said: "One of my concerns in writing the report was that we simply do not know enough about the surplus place situation in Wales.
"We don't know about the costs, we don't know about the advantages of reorganisation. I think there is a lot of management information that hasn't been collected and hasn't been analysed," he told BBC Radio Wales.