It was like being on the set of an inspirational Hollywood film about a visionary teacher who transforms the lives of disadvantaged African-American and Hispanic children in a run-down part of Los Angeles. The young woman leaping about at the front of the class, who had somehow got a group of 12- and 13-year-olds speaking fluent French, looked a bit like Emma Stone. If this was a film, she’d be a cert for an Oscar.

But this was no movie and I was in Wembley, not LA. The French class I was observing at Michaela Community School — a free school opened in 2014 by Katharine Birbalsingh — was the most impressive I’ve ever seen, and I’ve visited dozens of schools across the world, including some of Britain’s top public schools. Children on free school meals who had arrived wth a reading age of six were rattling off French verbs and sentences that would have shamed an A-level group. And this wasn’t even the top set!

I was suspicious at first — was this a dog-and-pony show put on to impress visitors? — but I popped into another class and then another. It was the same in every one. Children sitting up straight and listening in respectful silence, then a sea of eager, outstretched hands. It was like a model school showing just what it’s possible to achieve in the most challenging circumstances; the opposite of the dystopian classroom jungles in Channel 4’s fly-on-the-wall documentaries. Progressive educationalists claim that traditional teaching and strong discipline stifles children’s creativity and turns them into North Korean drones, but the children I saw could not have been happier or more engaged.

Even the lunch hour felt too good to be true. First, the children collectively recited poetry from memory — ‘Look on my works, ye Mighty, and despair’ — then, at the behest of a teacher, they discussed the topic of the day as they ate their lunch. In this case, the subject was the importance of dressing ‘professionally’, e.g., not wearing hoodies and low-slung trousers. At the end of the meal, pupils took turns to stand up and ‘give appreciation’ — thanking a fellow student or member of staff for teaching them a valuable lesson. One African-Caribbean boy stood up and said: ‘I’d like to thank Miss Dyer for showing me it’s easy to react in a crazy way if you’re accused of something you haven’t done, but it just makes people think you’re guilty.’

The government’s education reforms have been in the news this week following the announcement that all mainstream local authority schools in England must become academies, and the critics have been out in force. Once again, the dysfunctional public education system that New Labour bequeathed to the Tories in 2010, in which a fifth of children left school unable to read or do basic maths, is being portrayed as a golden age. According to these nostalgics, England had the best state schools in Christendom before Michael Gove and his Visigoths were let loose with axes and wrecking balls.

But Katharine Birbalsingh taught in a number of those schools and knows it to be a lie. ‘I’ll tell you what drives me,’ she said in her office overlooking Wembley Park tube station. ‘I failed hundreds of children in my lifetime because I was part of a system that failed children. I’m determined never to fail another child and if I can do that, Michaela won’t just save them; it will save me. It can be done. We just have to think differently.’

I’ve known Katharine since she bravely stood up at the 2010 Conservative party conference and spoke in support of Michael Gove. At the time she was the deputy head of a large south London comprehensive, and though no Tory, she had seen how bog-standard comprehensives had consistently failed the least well-off. Needless to say, she parted company with that comp soon afterwards. She earned a living as a journalist for a while, but I advised her to start her own school and, after getting nowhere in Labour-controlled Lambeth, she finally managed to open Michaela in Brent in 2014.

This school is nothing short of miraculous — a beacon of light made possible by Conservative education reforms. I hope that in three years’ time, when Michaela gets its first set of stellar GCSE results, Katharine will be invited to speak at the 2019 Labour party conference to explain how she and her staff have done it. Her opening line should be: ‘Look on my works, ye Mighty, and despair.’