The huge oak doors creaked open and I stood engulfed in a white mist so thick that I could not see my feet. Two intense red beams bore into my eyes. This, then, was the Harry Potter Experience. The lengthy column of cub reporters’ parents trailed up the cobbled lane through gate after gate, hemmed in by steep walls. On the challenge “Who are these intruders?” our minder Siobhan, keen to stay in role, called out to the Jacobite warrior ahead, “These are the Guardians.” The message, “They’re from The Guardian”, was relayed from battlement to lofty battlement. This was, after all, the launch of the new Harry Potter novel at Edinburgh Castle and even Jacobite warriors need to be media-savvy.

That afternoon I had watched my daughter Bethan and the TES Scotland correspondent Ailsa Floyd appear from behind trees in Princes Street Gardens as part of their photo shoot. After an epic overnight journey from Wales, where her family were on holiday, Ailsa was clearly very apprehensive. Ailsa’s father Chris explained that they were “just ordinary people”. For 48 hours that would not be true; our children would be very extraordinary indeed.

Most extraordinary of all was 14-year-old Owen Jones from Ysgol Glyntaf in Whitchurch, the envy of millions of children. The winner of an ITV competition, Owen carried out the weekend’s only one-to-one interview with JK Rowling. His mother Allison, who teaches English at Ysgol Glan Hafren in Cardiff, wanted him to ask former French teacher Rowling if she had any regrets about leaving the classroom.

Once the children were seated in the opulence of the Great Hall, the parents watched the midnight reading from the new book on television in the education centre. It did seem good and yes, it was funny, but my days of sitting on the carpet listening to stories are well and truly behind me.

All the parents had that proud glow on their faces that I have seen at awards evenings over the years. The only movement permitted was a slight gesture of the finger as each parent’s child appeared on screen.

On Saturday night I talked to June Hayman, a preschool teacher from Cape Town, who spoke passionately about the problems of ignorance, disease and poverty across Africa, the genocide in Rwanda and the eviction of the urban poor and white farmers in Zimbabwe. Her 14-year-old daughter Daniella had won a South African Sunday Times competition in which she had to explain what she would do if she had Harry Potter’s powers for one day: she said she would raise money for Aids education and to improve the lifestyle of a friend who had Aids. She equated Aids with Voldemort, the force of evil in the books.

Ailsa, still recovering from meeting Newsround’s Lizo Mzimba in Edinburgh HMV, was one of six children whose press conference contributions were broadcast on ITV.

Bethan’s other big question was for me: why were so many parents of the winning children teachers? I suspect we all have our answers.

My own claim to fame is that I saw most of the back of JK Rowling’s head as she got into her car at Edinburgh Castle. Last stop was Burger King at Waverley station, the spell well and truly broken.

Alan Roberts teaches science at Habergham high school, Burnley, Lancashire.

At the time of writing, he was on page 2 of the new novel