So, let’s take the apocalyptic scenario first. Television is evil. Parents should fear letting their children watch too much of it because they might end up, to summarise some experts, as obese couch potatoes with numbed brains, diabetes, possibly autism or ADHD (actually, can a couch potato be hyperactive? It’s an interesting thought). These will be children who expect entertainment on tap and are incapable of using their initiative, except to use the remote to switch from Tracy Beaker to New Scooby-Doo.

As someone with a three-year-old who is word-perfect on the Hastings car insurance advert and declares her favourite song to be “Let’s drift away, oooh . . . ooooooh” – the theme to the Surf advert – I shouldn’t be flippant about this subject. It is undeniable that a lot of children are watching an awful lot of TV when they could be doing other things such as reading, or kicking a football in the park, or talking to their parents, or making slug pies.

Dr Aric Sigman, a psychologist and member of the Institute of Biology, gives warning that there are real psychological and physical dangers associated with children’s overexposure to TV. Besides the nasties listed above, he has highlighted other possible side-effects such as cancer, Alzheimer’s and early puberty. He believes that letting young children watch as little as 90 minutes of TV a day could put them at risk of such problems, and that children under 3 shouldn’t watch it at all. The average British child watches triple this amount, with some 11 to 15-year-olds sitting in front of a TV or computer screen for seven hours a day.

“We are told that children need electronic entertainment or they get bored. It is not true,” he told MPs at a media conference. “Children have an infinite ability to entertain themselves, which TV seems to erode.

What children are exposed to under the age of 7, and particularly under the age of 3, is of paramount importance. It’s the under-3s we are most concerned about, and dramatically limiting the amount of TV watched between 3 and 7.”

But then there is the other, nicer, view: that modern children’s television is not mind-wrecking after all and it is largely of such high quality that it stimulates their imagination and teaches them not only literacy, numeracy and geography but morality, too – through programmes such as The Wonder Pets, which advocates teamwork via a story sung in operetta form; Dora the Explorer, which teaches basic Spanish; Numberjacks (maths); Nina and the Neurons (biology); and Fifi and the Flowertots, in which bad behaviour never triumphs.

It is true that last year a major study by the Johns Hopkins Bloomberg School of Public Health found that children who watch too much TV are more likely to suffer from behavioural problems (the American Academy of Pediatrics recommends that under-2s watch no TV, and that older children are restricted to no more than two hours a day). Another study suggests that putting infants and toddlers in front of a screen gives them irregular sleep patterns, and yet another that children’s resting metabolic rate decreases the more TV they watch, compounding the effects of sedentary entertainment, all of which makes uncomfortable reading for the busy parent who uses the TV as a childminder while she changes the beds.

Yet there is other research which shows that high-quality children’s TV shows improve children’s cognitive abilities, aid their speech and help them to forge social bonds.

Several US studies have indicated that children aged 3 to 5 who watch Sesame Street for an hour a day can recognise numbers, letters and shapes better than those who don’t. And here’s a sentence to warm the heart of any guilty parent: when 500 children who had participated in some of those studies were followed up as teenagers, those who had watched educational shows as preschoolers had higher grades, read more books, placed greater value on achievement and were more creative than those who hadn’t.

Isn’t it obvious that we should simply use some common sense about how much TV we let our children watch, and – doh! – never let them have TV sets in their bedrooms? Dr Ross Deuchar, a senior lecturer in education at Strathclyde University, says that letting your child watch, in short bursts, programmes that stimulate their imagination, and watching with them, does them a big educational favour. He says that parents should encourage young children to make links between what they see on screen and the content of their play.

“Some people see television as a narcotic [for children]. I don’t agree,” he says. “In the summer my three-year-old son and I spent a lot of time reenacting Dr Who outside. Programmes like Dr Who provide great stimulation for their imagination. There are super messages in programmes such as LazyTown. I have noticed that my son now wants to eat bananas because in LazyTown they call them ‘sports candy’.

“But we are very careful about adult television. We will not have EastEnders or Coronation Street on when he is still up.”

Dr Deuchar argues that TV should just be used wisely: “There is a difference between using it as a babysitting service and using it as a tool to stimulate learning. It is what you do as an adult around the TV-watching that counts.”

Further grist has been added to the pro-TV camp’s mill by a project run by teachers in Angus. Year Two pupils have been creating their own version of the TV show Deal or No Deal to improve their language and communication skills. The scheme, which is also being run by Scottish Screen, initially took place at Brechin High School and, according to an interim evaluation, teachers believed that it helped the motivation and attainment of pupils who might otherwise have needed extra support. “All teachers were aware of a significant impact on pupils’ listening and talking skills,” the evaluation said, “ and, by the second round of interviews, teachers reported developments in writing skills.”

The National Literacy Trust recently commissioned a study into concerns that television might adversely affect children’s language learning. It suggested that, on the contrary, in the right circumstances TV viewing by children aged 2 to 5 could help language development.

Dr Brian Young, a consumer psychologist based at the University of Exeter, says that there are three issues attached to children’s viewing: how it affects behaviour (ie, whether it makes them do things they wouldn’t otherwise have done, such as the craze for “Tangoing” people); whether it makes them anxious; and how they understand it. But he argues that there has been an overreaction to the issue of children and TV, and that strict rationing would not do much good. “Anything that is locked away becomes more desirable,” he says. “It would be a case of ‘I must see this’.

“Television is a resource like any other. It is like food – it can be good or bad. Viewing should be done in a family context, with the parents not just being there but watching and explaining what is happening.”

So maybe we should stand back and use our own judgment. After all, we are the ones who know our children best. While wall-to-wall television is obviously a very bad idea, some people have a vested interest in getting us all worked up about it. David Buckingham, Professor of Education at the University of London and author ofAfter the Death of Childhood, has said that parental fears about television and children are often exploited by politicians to deflect attention from, say, other causes of violence, such as poverty and racism. Others believe that all TV is evil, for both children and adults. Others want to sell a lot of books.

It seems that, broadly speaking, as long as you watch with the children, television is sort of OK. And, take it from me, there are worse ways to spend half an hour than in the company of Wow Wow Wubzy.

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