Sitting in Wembley Park Theatre feels like being back in school assembly. We’re sitting on stacked bleachers of felt chairs in what feels like a sports hall (actually an old X Factor studio). The programme has textbook puzzles and gobbets from pop-mathmo, Marcus du Sautoy. As it happens, the auditorium is packed full of school trips and the stage – an iridescent cube – is cast in grid paper, or Tetris cubes. The Curious Incident of the Dog in the Night-Time is, at its barest, a story about a boy (Christopher Boone, played by Connor Curren) leaving home. After ten years and a global tour since it opened at the National’s Cottesloe Theatre, it is back to the classroom for this only slightly saccharine story of family, trust and innocent bravery.