When John Craven took to the stage to accept a special Children's Bafta for Newsround on Sunday night, he asked the audience to put their hands up if they had ever watched the daily news bulletin. The response was predictable: a sea of raised arms.

Next year, the show will join Blue Peter, Panorama and Coronation Street in an elite club of programmes that have been broadcast continually for four decades. It is generally considered a noble BBC institution, breaking the story of the Challenger shuttle crash in the era before 24-hour news channels, and guiding British kids through the horrors of apartheid and the death of Princess Diana. And, of course, Craven's garish jumpers were items of sartorial legend; throughout the 70s and 80s these zig-zagged creations would often clash with the blue screen background images to create a surreal, migraine-inducing current affairs lightshow, the likes of which we'll never see again.

But as Craven and series creator Edward Barnes revealed on Sunday, the show had modest and precarious origins. It was originally proposed by just three members of the BBC newsroom who felt that children were often glimpsing frightening stories on the evening news, without understanding the context or meaning. However, the Newsround concept met with stiff resistance at the BBC. "Even within my own department there were people who said we shouldn't be doing this," explains Barnes, who was deputy head of children's television at the time. "Why should we tell children about disasters and massacres and murders? They thought it was violating children's innocence. There was a Victorian idea of childhood, that it is something to be protected and guarded – there was still a lot of that around at the time."

Fortunately, however, the concept had some powerful backers. "If it wasn't for one or two farsighted people, it would never have happened," says Barnes. "My head of department, Monica Sims, was crucial. And Paul Fox, probably the best controller the BBC has ever had, saw the point of it straight away."

The show was given an experimental six-week run, with Craven brought in from the newsroom to present. Forty years later, it's still here and retaining relevance even in an age where children garner most of their information from the internet. Barnes is, however, utterly unsentimental about the show, and its achievements – he won't be drawn on the key stories. "It's easier to think in that way if you're making a magazine programme," he says. "We were producing daily bulletins. News is gone when it's gone, and you're on with the next story. You just do the best job you can."

Asked about the current incarnation of the show, Barnes is complimentary, praising its editor, and current presenter, Ore Oduba. As for the state of contemporary children's TV, he gently bats the question away. "I was deputy head of children's programmes for eight years and head for eight years after that; I used to watch the whole of children's output every day throughout that period. When I left, I decided to switch off; watching it and not having control over it would drive me mad!"