Just as our memories of teenage years are shaped by the music that excited our imagination, our childhood is defined by the television programmes that we watched as we curled up under the blanket on our sofa.

Since the appearance of Andy Pandy in 1950, successive generations have come to associate their childhood with their favourite character. Not so long ago Teletubbies or Tweenies or Bob the Builder were the favourites. Today children who were happily fascinated by the Teletubbies find their anarchic pleasures through watching In the Night Garden. And when I took a poll of a dozen or so five-year-olds I was surprised to discover that their favourite fare was the American import SpongeBob Squarepants.

Of course, childhood today is less defined by one programme than in the past. Children are exposed to dozens of televison channels that transmit hundreds of programmes round the clock. How different from the mid-Seventies, when children’s shows were confined to an hour or so after school and Sunday teatimes. The Fifties series Watch with Mother was precisely that – an experience shared by parent and child. Until the Eighties, programme-makers assumed that their programmes, especially those targeting preschool children, would be consumed as part of an adult-child experience. It was taken for granted that mothers did not work and that parents would serve as volunteer sounding boards and interpreters for their children.

This was before the existence of 23 channels that compete for your child’s attention. The appearance of video and DVD players – digital babysitters – has weakened further the custom of family viewing. Parents can now sit their toddlers in front of the video to watch an episode of Teletubbies while they chat about grown-up stuff. And a good thing too. In the era of the working mother it is a godsend to be able to access programmes when you need them rather than having timetables scripted for you.

Until the Seventies, children’s viewing was scheduled by the programme makers. Today, with virtually non-stop wall-to-wall children’s TV on dedicated children’s channels, the responsibility for scheduling has been handed over to the parent. This is a responsibility that parents find difficult to exercise, as revealed in the shocking results of a survey by the market research agency Childwise, which this week showed that British children spend an average of five hours and 20 minutes watching TV every day. A constant war of attrition between children and their parents has led to the gradual diminishing of parental supervision and scheduling. Television programmes reflect this trend and engage directly with their youthful audience. Gradually the idea of family viewing has given way to children’s viewing.

The routine of Watch with Mother has become anachronistic in an era where adults are self-consciously excluded from children’s programming. This shift is noticeable even with programmes oriented towards the very young. In the fantasy world of the Teletubbies the characters gurgle and make pleasant, childlike noises but do not talk or communicate in ways comprehensible to grown-ups. The Teletubbies were conceived to communicate with and interact with youngsters and to exclude adults.

In many ways the chaotic fantasy world transmitted through programmes such as Teletubbies to preschool kids offers the most exciting genre of children’s television. The BBC’s In the Night Garden represents the best of this type – a surreal and magical world where children can freely imagine themselves. Here, too, the characters have their nonsense signature sounds that might confuse the adult but which delight infants and toddlers. To the bemusement of uncomprehending parents, the bizarre undersea creatures who inhabit the world of SpongeBob Squarepants also succeed in exciting children’s imagination.

What’s good about these pre-school programmes is that they engage, delight and entertain. So there is a lot of great kids’ TV around but there is also a discernible tendency to be suspicious of children being entertained for their own sake. Every toy or gadget targeting youngsters is marketed on its alleged developmental merits. As with toys, the educational benefit of TV shows is one of their selling points. It is just about OK simply to entertain babies and toddlers. But programme-makers targeting children aged 3 or 4 feel uncomfortable about simply giving their audience a good time.

The radical transformation of childhood in recent decades has been strikingly paralleled through children’s television. Most adults are, of course, aware that the didactic ethos associated with the BBC’s 1960s programme Blue Peter has given way to a more in-your-face, we’re-all-mates orientation of the current crop of children’s presenters. But old-fashioned Reithian paternalism has been succeeded by an ethos that is no less prescriptive.

This was brought home to me just over a year ago with the issuing of the earliest episodes of Sesame Street on digital video. The DVD, Sesame Street: Old School now comes with an unexpected health warning – it is for adults only! Apparently episodes of this programme that delighted a generation of children in the late Sixties and Seventies are far too risky and gritty for the fragile little darlings of today. One reason is that they send the wrong message. Carol-Lynn Parente, the executive producer of Sesame Street, gave the example of Alistair Cookie and the parody of “Monsterpiece Theater” as an illustration of the new risk-averse attitude towards programming. Apparently the sight of the Cookie Monster holding a pipe that he later gobbles up is far too challenging for 21st-century children.

But more importantly, according to Parente, the scene “modelled the wrong behaviour”. When I asked a couple of friends involved in children’s television in the UK they all concurred that “sending the right message” had become the principal preoccupation of programmers. One friend confided that she was criticised heavily for depicting a scene where laughing children were seen stuffing themselves with chocolate. Her executive demanded that the scene be redone showing happy kiddies munching apples and grapes.

Edgy and gritty realism has been gradually abolished from children’s TV. The Story of Tracy Beaker stands out as an honourable exception – it is one of the few programmes that attempts to engage a young audience with social reality. But the kind of gritty drama associated with Grange Hill’s golden period in the mid-Eighties is conspicuously absent. This series’s popular storyline about Zammo and his heroin addiction is clearly off-message for programmers obsessed with sending the right signals to impressionable viewers. Paradoxically, programme-makers insist that they are committed to letting children speak for themselves. But they find it difficult to reproduce the anger and rebelliousness displayed by the feisty teenagers at Grange Hill.

Those who believe that the early episodes of Sesame Streetare strictly for adults are likely to love Lazy-town, a programme committed to all the worthy contemporary fashionable causes. Stephanie is a heroine in Lazytown. She is on a mission to convince her new friends to become active instead of staying at home and vegetating in front of video games. Another character, Sportacus, is something of a super-healthy hero – a role model for those crusading against child obesity. Robbie Rotten is a depraved antienvironmentalist predator who tries to convince naive youngsters to eat junk food. Lazy-town manages to make 1950s and 1960s programmes such as Crackerjack or 1980s offerings such as Postman Pat appear experimental and open-minded.

Programme-makers often insist that their programmes must give pride of place to the voice of young people. Children are often flattered and frequently represented as far more savvy and knowing than grown-ups. Presenters no longer attempt to assume the authority of adulthood nor self-consciously educate their audience. In the Fifties and Sixties, presenters tended to be formal teacher-types with proper BBC accents. Their narration for clunky puppet shows such as Andy Pandy or Muffin the Mule would invariably begin with “Now, children, do you know . . .?” Today the word children has been virtually abolished from children’s television. Many shows designed for older children and preteens such as The Simpsons present a world in which grown-ups are characteristically dim and insensitive and children are sussed, streetwise and clever.

With a few honourable exceptions, children’s television reflects a crisis of adult authority. The diminishing valuation of adult authority undermines even the potential to educate. Serious children’s television is one of its casualties. It is unlikely that the more challenging children TV shows of the 1980s – Think of a Number – can be replicated today. And no doubt if the austere and far too serious 1960s general quiz programme Top of the Form were to be released in a DVD format it too would come with an adults-only certificate.

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