Child Genius, Channel 4/Agnetha: Abba and After, BBC One

Nobody said it was easy being an infant prodigy. Take Hugo, ranked in the top 0.4 percent of the population. He knows everything there is to know about train engines, train stations, rail networks etc, has them committed to his photographic memory. At 10 he is, basically, on some sort of spectrum, and he knows that too. “This is my brother Oscar,” he said. “He’s a more normal child.”

Is it just coincidence that Child Genius (****) kicked off on the day Michael Gove announced details of the new I-level? Gove would approve of the star participants, who are all strong on maths and facts. They were competing in this year’s Child Genius of the Year award. It's a sort of Britain’s Got Talent for people who don’t watch Britain’s Got Talent. They’re too busy reading books. Or smelling books in the case of Shrinidi, a young Indian girl who at three could identify every flag in the world and has twice been under-12 world Scrabble champ. Shrinidi loves books so much she sometimes licks them too, said her mum. She didn’t lick Fifty Shades of Grey on the grounds that it's not got any grey in it. “Psychologically," Shrinidi lisped, "it’s a bit taxing being really clever, I guess.”

Then there’s Josh, whose cabinet is laden with chess trophies, not all of them plastic. His American über-mom enters him in 200 chess matches a year. The plan after 10,000 hours is to make him the youngest ever chess grandmaster. “I have focussed a lot on the chance to celebrate Josh,” she purred. “The chance to win is a very exciting moment for a mother.” Out of the mouths of babes' mums. And you thought these people could only be found court-side at tennis grand slams.

Another tiger parent hailed from Hong Kong, and was now living in Devon and working to turn his 10-year-old Longyin (pictured) into a winner. This involved a routine of exercise, homework, domestic chores and quizzes while playing ping pong. “What is the capital of China?” his dad fired at him while serving. I know that one. The freak was the father, the child wonderfully unaffected by this potty regime.

My favourite parents were Hugo’s. They have made it their business to remind Hugo that being clever doesn’t make him a better person, although he appears still to need some convincing. “He is in the top five percent of irritating children,” said his mum, in front of him. They’ve made him take up the trumpet so that one day he might join an orchestra and possibly even shag a woodwinder.

In the meantime opportunities for socialising were offered by Mensa’s annual f̶r̶e̶a̶k̶ ̶s̶h̶o̶w̶  competition. All the parents fondly hoped that meeting other geniuses would be A Good Thing. The kids weren’t so sure. Their focus was more on beating the opposition to a pulp ("I do believe you'll be hearing a bit more from me," promised one), and in the event Channel 4’s filmmakers haven’t so far found any evidence that a single genius has said a single word to another genius. Apart from two siblings who hate each other. “We can support them,” cooed an adult genius from Mensa, “and help them to become the best person they can be.” If only some of the parents were on the same page. Josh the chess player, who vomited all over the car on the way, got one question right. “I love you for trying,” lied his gutted mom.

We know all about Agnetha Fältskog and the end of her long silence. Agnetha: Abba and After (***) was the latest interview, and it wasn’t especially revealing if you’ve heard or read any of the others, but there was some lovely archive footage of Swedes jiving in the 1960s and Abba in their considerable pomp. Bjorn and Benny and Sir Tim were on hand to say bits and pieces, and only Frida could not be persuaded to speak about Abba in general and Agnetha’s prize-winning rump in particular. One can only guess at her reasons. We also watched Gary Barlow fly over to Sweden to record his part for the duet on the album. For some reason Agnetha wasn’t there. Had to see a man about a dog or something. When they did finally meet, he asked her if she’d one day perform with him live. She didn’t say yes. Perhaps she saw the Diamond Jubilee concert.

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