The BBC children’s documentary series Trading Places is based on the formula of a brief life-swap between members of well-defined and clearly contrasted groups.

The current series started (on April 4) with pupils at a ballet school in a swap with a group of Yorkshire Army cadets: in the first programme, we watched pupils used to the discipline of the barre being subjected to the equally demanding but very different rigours of an army assault course. In the next programme (April 11) the cadets put on ballet shoes and leotards. One of the underlying assumptions of the series is that the groups will end up with greater respect for each other.

In many countries, moving from one school to another might not be expected to provide such a dramatic change of circumstances, but in Britain an exchange between state and independent pupils was bound to occur to the makers of such a series.

The idea dates back at least to the Boulting Brothers’ 1948 feature film, The Guinea Pig, in which Richard Attenborough plays a tobacconist’s son who wins a scholarship to public school and needs an accent, table manners and attitude makeover before he is accepted.

Some things have not altered since 1948, but - as the films broadcast this week and the next show - a great deal has. Six Year 9 pupils from Kenton comprehensive in Newcastle upon Tyne were sent for a week to Dauntsey’s, a mixed fee-paying school in Wiltshire; after that, their families played host to six pupils from Dauntsey’s on a return visit. The exchange dispelled some myths, but may have confirmed a few prejudices.

Though there is still a huge gap between the private and state sectors in British education, the two sides are better acquainted with each other than they were 50 years ago, if only because of television (think of Grange Hill). This week’s programme follows the Newcastle pupils to Wiltshire. Ironically, one of the first things that strikes visitors about life in an “exclusive” school is the lack of privacy in the showers and dormitories, the “private” element in British fee-paying education being traditionally to do with privation rather than with keeping anything to oneself.

There are compensations: the food is good, the facilities are superb and the school has its own boat. Experiences in the classroom confound expectations.

Nicholas Allan from Kenton (one of three participants in the exchange that I caught up with this week, six months after filming) anticipated a lot of homework at Dauntsey’s but found his counterparts there much less worried about academic achievement and exams than he had supposed.

On the other hand, Nicholas feels that his own school provides better preparation for real life: “In Kenton, you get the good people and the bad; at Dauntsey’s, it’s pound;4,000 a term, so no troublemaker is going to pay that.”

The only fights he saw at Dauntsey’s were pillow fights (which, he assured me, were not staged for the camera) and indiscipline was mainly confined to disrespect for the lights-out order.

When Chlo Midwinter and her friend, Fiona Bullen, went to Newcastle (their visit will be covered in the April 25 broadcast) they were given little homework, but their hosts laid on a full programme of evening entertainment. They had expected Kenton to be a lot rougher than it was (Grange Hill is perhaps to blame here), but were surprised, even so, by the extent of security in the school, with pupils being locked out if they were late for lessons.

Sometimes the girls felt “quite insecure”. Classes were larger, teachers did not always know the names of all the pupils and, in general, pupils at Kenton seemed to have less respect for staff.

They had no difficulty in making friends. “I learnt that, whatever situation children are put in, they will get along,” Fiona told me. “I think the boys found it harder than the girls. Boys are not so open. It’s more difficult for them to find things to do together.”

The difference is reflected in the extent to which the pupils have kept in touch with each other since the exchange: Chlo and Fiona still write to the Newcastle girls with whom they stayed, and occasionally talk on the phone. Nicholas has had less contact with Dauntsey’s pupils, although he enjoyed his week there - “I was treated like a king” - and was offered a chance to stay on with a scholarship covering half the fees. He decided that, at 14, the break with home would be too great. But then Nicholas is a Newcastle United season-ticket holder.

There may be few general lessons to be drawn from the experiment, if only because the pupils who took part were atypical: bright, sociable, intelligent and representative of the best in their respective schools. And don’t expect too much sociological analysis in the commentary, which is pitched at a young audience. The films seem short, given the amount of material that must have been collected in making them last autumn, but they are watchable and jolly.

And it is clear from talking to these three young teenagers that the effects of the experiment on them have been profound. Nicholas, Fiona and Chlo would do itall again.

Trading Places. BBC1. April 18, 5.10-5.35pm. Best of the restHistory Zone Films is what BBC2 is now calling its flagship history strand, Timewatch; heaven knows why. The good news, however, is that so far HZF (or: The Programme Formerly Known as Timewatch) seems to be little different from its predecessor (which was consistently excellent).

This week, following an edition of One Foot in the Past about buildings inspired by animals - memorials, kennels, stables and Berthold Lubetkin’s penguin pool at London Zoo - HZF traces the history of the Royal Menagerie, which existed from medieval times in the Tower of London.

Many of the animals then were gifts from foreign visitors or ambassadors, including a white bear which arrived in 1251 and an African elephant which joined it four years later after a crowd-pulling journey from the Kent coast.

The most significant revelation in the film is how attitudes towards animals have changed. In the 18th century, visitors to the menagerie who wanted to avoid the admission fee could bring along a dog or cat for feeding to the lions. It was only in the 19th century that Britain brought in legislation against cruelty to animals.

The menagerie closed in 1835 and its animals were transferred to Regent’s Park - which brings us back to the penguin pool.

History Zone Films:Kings and Beasts BBC2. April 15, 8.05-8.55pm. Sean O’Callaghan and Alex Calderwood, two former paramilitaries in Northern Ireland who have now renounced violence, are the subject of a sober, well-made documentary on the Discovery Channel. Both men talk about the killings that took them to prison, but the film focuses on their motivation and the upbringing that predisposed them to take part in such violent acts.

Sean O’Callaghan was head of the IRA Southern Command; now, as the most highly placed informer to turn against the organisation in its history, he condemns the IRA for what he sees as a romanticised obsession with violence. He recalls his childhood, in a fiercely republican family, and revisits the bar where he shot dead a member of the RUC. Archive film recalls the historical background to the Troubles.

Alex Calderwood beat a Catholic man to death: he remembers growing up on the Shankhill Road and wanting nothing except “to kill Catholics”. Now he runs cross-community projects for schools in Belfast.

Neither man’s story is unfamiliar, but together they contribute to an analysis of the origins of hatred and theways in which it is sustained from one generation to the next. The film would provide useful and unsensational material for use with older children.

Fighting Hatred. Discovery Channel. April 17, 10-11pm. Every afternoon next week on Radio 4, Philip Dodd, director of the Institute of Contemporary Arts in London, explores the use of children as symbols and inspiration in 20th-century art - though he starts on Monday with theRomantic view of the child in the early 19th century andthe idea that children are more spontaneouslycreative and perceptivethan adults.

He notes that the child has also been a powerful source of anxiety, in such works as Henry James’s The Turn of the Screw or Ravel’s Les Enfants des sortil ges, and that this may be translated at another level into concerns about juvenile delinquents, child killers and the abuse of children.

Troubling Children. Radio 4. Daily April 17-April 21, 3.45-4pm. Next week: the term ahead on Schools TV. Listings return on April 28