On Teddy Bears' picnic day, handing out the bear-shaped crisps is an opportunity to practise counting up to five, just as the pile of gravel dumped in the back garden provides a different opportunity, for digging, raking, observing insects and working as a team. A dead blackbird that one of the boys finds in the barn is put on a table for the children to draw and paint, and this in turn prompts a thoughtful, child-led discussion about the function of bones.
With the School Curriculum and Assessment Authority about to publish its consultation document on desirable "outcomes" for pre-school children and appropriate ways to achieve them, Hilary Renowden's model of active, independent learning, combined with care, has much to offer.
The nursery is both free-ranging - encouraging children to follow their own interests and make their own decisions - and carefully structured, to ensure that they experience all areas of the curriculum. Staff are trained (many of them by Hilary Renowden herself) to observe the development of each child, helping where necessary, and tailoring a learning programme to fit each individual.
Mrs Renowden's own "outcomes" are set out clearly for parents and staff: the achievements of a three-to-four-year-old, for instance, should include counting out five objects, knowing colours and shapes, and beginning to form numbers and letters, as well as taking turns and sharing, contributing to group play, and helping younger children.
Now 56, with two grown-up daughters, Mrs Renowden almost ended her teaching career six years ago, after 30 years' experience in state schools. She took early retirement in 1989, disillusioned by four years as head of a primary school in Clwyd, serving a deprived new estate where the promise of jobs had failed to materialise.
"I had to be everything for those children, as well as coping with limited resources and the endless bureaucracy and red tape, and in the end, it was beyond me. I came out vowing I would never work with young children again, " she says.
But after a year's rest and a spell doing supply teaching, Mrs Renowden's passions were reawakened and she decided to open her own nursery - "to be something as near perfect as I could make it". Her ideas were much influenced by the Scandinavian nurseries she had visited while running an early years diploma course in the early 1980s.
"They were very child-centred, but with a strong, underlying structure, and there was a great emphasis on the environment inside and outside the nursery, " she says.
Inside, the aim was to make the nursery as close to the child's home experience as possible, with, for instance, full-sized tables and real paintings on the wall. Outside would be a range of wooden equipment, flexible in its design to suit different ages and activities from climbing to making houses.
So it was no surprise when Mrs Renowden made over the ground floor of her family home - a largish post-war house set in half an acre of land - to the new nursery, and moved to live upstairs with her husband. Wallpaper, floor-length curtains, pot plants and a piano all contribute to the comfortable, non-institutional air of the nursery, and the sunny conservatory, where the Renowdens had planned to sit in their retirement, is now given over to train sets, books and a writing and drawing table.
Painting, sticking and gluing are constantly on offer in the "wet room", and outside there are bikes, water, sand, a "mud-pie" corner, all manner of dens, and even a couple of chickens. An old dog kennel has recently sparked some highly imaginative play, Mrs Renowden says. "It's very important to give children a bit of privacy."
Apart from circle time, story time, and breaks for drinks, there are no set times for particular activities, and the children are free to move around as they choose, with staff gently making sure that they try a range of things.
About 56 children, from two to four, attend the nursery every week, with up to 22 in each session, morning or afternoon, and 20 per cent doing daycare hours of 8.00 to 5.30, at Pounds 13 per day. Eight paid staff, most of them mothers trained by Mrs Renowden, divide the day among them, working in two teams. Only Mrs Renowden herself is at the nursery all day every day, observing all that goes on.
The children clearly benefit: they appear relaxed and well-motivated, and their paintings, drawings and "copied" writing attest to their growing powers of self-expression. Believing that this approach to education and care could begin at an even earlier age, Mrs Renowden has opened her old stable block as a unit for babies from six months to two years.
"There is a happy atmosphere here - it's like a big houseful of kids," says Sue Pritchard, whose son Thomas has been at the nursery for two years. "I like the fact that the staff are genuinely interested in the children's development, and don't see it as just a job."
"My son has got a lot more confidence now," says Michelle Watmough. "The children here are encouraged to express themselves and they are not stamped on."
Lesley Abbott, principal lecturer in early years at Manchester Metropolitan University, has chosen Hilary's nursery as one of 12 case-studies in a two-year research project on under-threes. "This nursery is an excellent model of both training and practice. Good provision depends not so much on equipment, but on the insight and understanding of the staff. Here, the quality of interaction between staff and children is very good, and the children are given a sense of independence and ownership."
If the nursery has one failing, it is perhaps only that Hilary Renowden, with her commitment and energy, has made herself indispensable. But her methods and ideas deserve a wider audience.
"When I'm very tired, I sometimes ask myself, why am I doing this? But I've done it to prove that it can be done. These children are full of confidence when they go to school: this kind of nursery really does work."