Not so long ago, country children helped with the harvest, watched and maybe even worked with the shepherd on the hillside. Now knowledge of agriculture, like pretty much all other types of knowledge, has to meet defined objectives. Among the more imaginative ways of acquiring rural knowledge is to visit Ewe-phoria and the Agri-Theatre of Wales, at the Denbighshire hill farm of Aled Owen. Children can find out about 13 breeds of sheep and watch as Aled and Bob the Border Collie move flocks around the hills. Aled went on an Agricultural Training Board course at the age of 17. He is now World Sheepdog Trials Champion, winner of the One Man and His Dog competition, and twice International Supreme Champion.

Bob is one of his best dogs and, on a clear day, he can hear and obey commands from up to a mile away.

Aled and Bob demonstrate with a flock of about 30 sheep. They can handle 400, and Aled can command four dogs at a time. The manoeuvres include gathering (collecting into a group), driving (moving sheep away), balancing (positioning) and shedding (leaving part of the flock behind). Bob is alert and eager; when Aled gives the whistle for the out-run (the first order, to fetch the sheep), Bob runs directly to his position and crouches down to await further orders.

First, they must shed one of the ewes and a lamb and drive them to a corner of the field. Easy! Next, the flock is gathered, balanced, and driven through the gate. Speed is crucial: if it is too slow or too fast, the sheep will scatter and become confused. The whistles are short, frequent, and so subtly different that the unaccustomed ear can hardly distinguish between them.

A major factor is the frequency with which the dog must stop altogether, so that it does not frighten and disperse the sheep. The moment for giving orders is also critical. “The thing is to understand the sheep’s next moves”, says Mr Owen. “You can train dogs to pick out a leader, and work with that.” A good stockman can also pick out sheep that are unwell or wild, and shed them.

The Agri-Theatre is a converted barn with a stage of wooden terraces where rams parade while we learn about the characteristics of each breed, whether valued for meat or for wool, and the kind of terrain they thrive in. The Blue Face Leicester is very popular; Welsh mountain sheep are exceptionally hardy and can produce lambs that grow bigger than the mothers; Texel sheep from Holland are all white and very pretty; the French Charolais look rather peculiar; Cheviots, unusually, are valued for both meat and fleece.

The mystery of the shepherd’s crook is revealed: its length is for walking in the hills; the crooked top piece is made from the horn of a sheep, and used for catching lambs and hanging a lantern on at night. According to season, there may also be lambs or puppies to see, or a demonstration of shearing at a rate of one sheep every 90 seconds.

Older pupils learn about the economics - the price of wool, the rate for shearing, what sheep eat and how much of it, how lambing takes place. Once, there were 5.5 million sheep in Wales, and more than 50 breeds in the UK.

Now, a 100-acre hill farm with 300 sheep, such as the one Aled Owen inherited, is no longer viable. Everyone is leaving: the average age of a farmer now is 58.

All age groups have visited Ewe-phoria, right down to nursery children, for whom the dogs will shepherd ducks into a pen.

Demonstrations 11am and 1pm, Easter-October. Lambing days in April. Groups from 10-60, one adult per 10 children: pound;2.80 per child, pound;3.90 per adult

Ewe-Phoria, Glenrafon, Llangwm, Corwn, Denbighshire LL21 ORE. Tel: 01490 460369. www.ewe-phoria.co.uk