Teacher leaders have warned that unqualified staff must not be used to make the Assembly government’s flagship “learning through play” programme work.

The foundation phase for three to seven-year-olds has been hailed a great success in its first pilot year, but schools are concerned there will not be enough funding to employ the extra qualified staff they need.

The pilot, which involves 41 early years’ settings, began 12 months ago with pre-school, nursery and reception children. Some schools and playgroups, however, are still waiting for funding to adapt play areas, while others are drafting in unqualified assistants to meet the target ratio of eight pupils to one adult.

The General Teaching Council for Wales said the philosophy behind the foundation phase was sound, as it expanded the learning opportunities and social skills of young children. But chairman Mal Davies expressed concern that funding levels may not be adequate for upgrading the skills of adults working in early years.

“The council will continue to support the initiative as long as a qualified, registered teacher is responsible for planning and delivering the activities for each and every class, and there is adequate provision of qualified and experienced classroom support staff,” he said.

But pre-school playgroups say they are struggling to recruit and retain staff, who can get better pay and conditions working in infant and primary schools. The problem is even more acute in Welsh-medium settings.

And one school source told TES Cymru: “The Assembly is not prepared to give funding for all of the support staff to be trained nursery nurses so we have classroom assistants instead.

“That makes it even harder to find enough staff to meet the adult-pupil ratios because they are so badly paid.”

All pre-school playgroup staff must have qualifications for working with young children by 2008. The plan is for all foundation phase workers to be appropriately qualified, but the Assembly government has not yet set the standard required or a timetable.

Gethin Lewis, secretary of the National Union of Teachers Cymru, said the foundation phase was an excellent scheme but should not be developed “at the expense of the de-professionalisation of qualified staff”.

Most schools say they are working on a 1:13 adult-to-pupil ratio with Year 1 children, who joined the pilot this term. The Assembly is aiming for a 1:8 ratio across the foundation phase by 2008. But education and lifelong learning minister Jane Davidson has previously warned this level of staffing will be subject to evaluations showing improved outcomes for children.

An Assembly government spokesperson said it had fully funded the extra staff needed to match the required ratios. “Findings from an evaluation of the pilot, along with the availability of appropriate levels of funding, will inform the full roll-out,” he added.

Another challenge is the provision of adequate play facilities. Children at Ysgol Ty Mawr on Anglesey still do not have proper access to the outdoors, a key element of the learning programme, while Kitchener primary in Cardiff has used money from its own budget to build three different play areas for the foundation phase.

Head Jane Evans said spending will reach nearly pound;38,000 by next year, when the third area is developed for Y2 pupils: “It’s taken a lot of money but we wanted different activities to suit each age group, and the children love it.”