On a hill outside Bristol a rounders game is disintegrating into a squabble over the rules. Time for some adult intervention. "We're not here to argue, we're here to have fun," Ron Langley reminds the young players.
It's a rare moment of tension in an otherwise harmonious day. The eight children, all from a Year 3 class in Cutler's Brook Junior School in the city, are enjoying a day out on the spacious slopes of Ashton Court park in Clifton, under the supervision of three adult volunteers.
Beneath all the fun and games there's a serious purpose. The children are all members of the Tiger Club, one of 10 after-school therapeutic activity groups in Bristol run by the National Pyramid Trust. Other groups are operating in the London boroughs of Hillingdon and Hounslow, and in South Glamorgan.
The clubs are designed to help those "invisible" children whose individual needs may not be immediately obvious to hard-pressed teachers in the classroom, but who may become problems later. They are also giving PGCE students valuable experience of relating to young children on an individual basis.
The idea for this simple but effective preventive project came from Kay FitzHerbert, an experienced educational social worker.
Her concern was not with the disturbed or special needs child, who will already have been picked up by the system, but with the quietly unhappy, the misfit, the anxious, the non-joiner.
"We try to select the quieter, more reserved or withdrawn children, who get overlooked by both their peers and teachers," says Eleanor Armitage, the Bristol project manager. "In the smaller-scale, safer environment of the club, with a high ratio of adults to children, they're able to express themselves more boisterously."
There's certainly little sign of inhibition or withdrawal on the Tiger Club's outing. The children join gleefully in the Frisbee-throwing, football and parachute games, and demand piggy backs from the adults. After a picnic lunch there's a nature walk in the nearby woods, and excitement at finding a tree trunk that can be used as an imaginary boat.
The children have chosen their own club name, and are half way through the 10- week process - known familiarly by the organisers as Forming, Storming and Norming. They appear to gel as a group, with only the odd complaint about sharing or taking turns. And the volunteers have noticed significant changes.
One girl who used to keep herself very separate now joins in quite comfortably with the activities. A very shy boy has gradually become chatty and lively. Another boy, with poor concentration, is much less attention-seeking. Significantly, the children's class teacher has also noticed a change in these children's behaviour - including the fact that they smile more.
Kay FitzHerbert got the idea of the club from Newcastle, where short-term therapeutic groups had proved effective for primary children on the "at risk" list. "It was like a fertiliser, the kids just got stronger," she observes.
Theoretical backing came from the American psychologist Mortimor Schiffer, who has pointed out the desire of children of this age to be "one of the gang", and the need for an environment where this hunger could be properly satisfied.
Kay FitzHerbert tested out the club idea in Hounslow, west London.
Later with money from the Social Science Research Council, she followed up the children in their third year of secondary school. Her findings suggested the experience had significantly helped them academically or socially, or both.
The success of the clubs persuaded Hounslow Borough Council to take them over as part of its educational support service. The projects in Avon and Hillingdon are pilots, and have attracted Pounds 58,000 from the Department of Health over three years. Those in Wales have Pounds 64,000 from Children in Need for the same period.
Sessions take place either on the school's premises, or nearby and last for 90 minutes. The adult-child ratio is never more than 1:4. There are games a-plenty, but also practical activities such as cooking and mask-making. One club made the mistake of offering opportunities for reading and writing: children quickly backed off such "schooly" activities.
But there is more to the project than the clubs alone. Children in participating schools are screened at 7 or 8, to check on their work progress, attendance, physical development, social skills and "personal adjustment" - covering items such as concentration, motivation, adaptability and level of self-esteem.
This process has uncovered children needing other kinds of help, such as counselling. But the main aim is to select the children who might benefit most from a place in the club and to create a balanced group, without siblings or best friends put together.
But it also gives teachers a rare opportunity to discuss the children's needs with other professionals and support agencies. They do this at two inter- disciplinary meetings: the first decides what action to take on each child, the second reviews progress, and includes feedback from teachers and club leaders.
Many of the leaders are PGCE students, who see a stint as a trained volunteer as a useful antidote to working with large classes on teaching practice, or a chance to drop down the age-range. Kay FitzHerbert speaks highly of them. "They're enthusiastic, imaginative, and diamond wonderful," she says. "They just love building up relationships with the children."
Fiona Walker, one of the Tiger Club volunteers, certainly relishes the opportunity. Still recovering from a piggy-back session, she says: "Teaching practice can be so frustrating, but here you can give them so much more attention. It's also good to be in a role which is neither teacher nor parent."
The opportunity will soon be available to more young teachers: this autumn Bristol University includes the work as a module in its PGCE course, as an alternative to special needs. Meanwhile, the pyramid seems to broaden its base, with Wandsworth and Berkshire interested in taking up the idea.
Further information from the National Pyramid Trust, 12 Brierley Court, Church Road, London W7 3BN. Tel: 0181-579 5409