Almost all nursery, infant and primary schools teaching the foundation phase sailed through inspections last term, despite staffing and funding shortages, TES Cymru analysis shows.
Some schools have also started to teach the play-led curriculum to post- reception class pupils, although it will not be compulsory for under- sevens until 2012.
Estyn, the Welsh inspectorate, also says nurseries are storming ahead with the popular learning method. Most are a year ahead of schedule.
According to the 83 published reports on primaries, infant and nurseries inspected in the autumn term, just four were struggling to get to grips with the new curriculum, based on structured play and similar play-led schemes abroad. Only one nursery, Cylch Meithrin Nant-y-groes in Carmarthen, was judged to be unprepared for the new curriculum. Inspectors said three others would improve if staff received more training.
The sterling performance of schools comes despite funding shortfalls acknowledged by the Assembly government.
A highly critical draft report, released by an Assembly committee last summer, blamed the cash crisis on a "chronic system failure" in communication between local authorities and the government. The national introduction of the new curriculum in reception was delayed for a year as a result.
However, Jane Hutt, the education minister, secured more funding for the foundation phase for this academic year after an outcry by teachers' unions.
Many schools went ahead with introducing it for reception pupils, in some cases without the recommended 1:8 teacher-to-pupil ratio. They said they did not want the children to miss out on the popular scheme, which is widely seen as the answer to raising literacy and numeracy skills, especially among boys.
At Caldicot West End Infants School in Monmouthshire, inspectors said the reception class was ready and raring to learn.
Gillian Bray, its head, said a new outdoor area was having a great effect. "The classes are buzzing. Children are investigating and becoming more independent. They're willing to try things for themselves."
The school plans to extend the foundation phase to Year 1 pupils next year.
Sally Jones, foundation phase training and support officer for Monmouthshire, said many schools were ahead of the game.
"Most reception classes in our authority are working well on the foundation phase because, initially, they thought it was going to happen. Even if staffing sometimes isn't sufficient, everyone is seeing the benefits of it."
Ely and Caerau Children's Centre, near Cardiff, was the only one to receive seven grade 1s, the highest possible inspection marks.
Carolyn Asante, the head, said the centre had benefited from specialising in early years.
"We look very closely at different children and what engages them, and than we try and take it one stage further."
An Estyn spokeswoman said early-years education was still in a "transitional phase" but that the reports were positive overall.
"We would expect to see some of the good features of foundation phase methodology in the planning for key stage 1," she added.
WHAT THE INSPECTORS THOUGHT
Treorchy Primary, Rhondda Cynon Taf
"Children were admitted to school with less developed skills in language and personal and social development than in previous years. However, they quickly make good progress in the foundation phase."
Penygelli Primary, Wrexham
"Children in the foundation phase make exceptionally good progress."
Garth Primary, Bridgend
"The school has begun to develop provision for the outdoor learning for children in the foundation phase and makes good use of the limited facilities available."