Allan Ahlberg has written more than 140 books. He ought to be extremely tired: I can only say it doesn't show. His latest pop-up book, illustrated by his daughter Jessica, is characteristically spry, witty, irreverent and joyous, an inventive series of variations on the Goldilocks story to be chuckled over by fortunate children and pawed repeatedly with sticky fingers.

For it's a book which demands repeated use. The daisy-chains of sweet little pictures (similar in style to those of Jessica's late mother Janet) are full of heart-warming details waiting to be spotted and shared. The stories are the same  fresh and bold, with a delightful line in wordplay. The book performs a very clever trick: honouring the original Goldilocks story at the same time as taking it apart, tossing the bits up into the air and  with a squirt of Ahlberg magic  making something new. There's a touch of the Shreks about the Ahlbergs' attitude to fairytales, and their Goldilocks riffs are adorable, anarchic and very funny.

Here  of course  is Goldilocks and the Three Bears. Here also is Goldilocks and the 33 bears (including quite a lot of skinny teenage bears in hoodies, flat-peaks and anti-fit Levis). Very nice. Then we have Goldilocks and the Three Bliim. Bliim are very like bears, except they're green with many tentacles, live in troods (spaceships) and when they get cross shout things such as: "Who's been doddering my spootz?"

In addition we have Goldilocks and the Stroppy Furniture (told from the point of view of the chair on which Goldilocks tries to sit, the bowl out of which she tries to eat porridge, and the bed in which she tries to sleep), Goldilocks and Everybody (very mad and cramped) and Goldilocks and Nobody At All (with exactly the right sort of satisfied sleepiness at the end of a very busy storytelling day). All this plus a tiny book within a book: a pantomime put on by a whole cast of fairytale characters in full make-'em-laugh, get-'em-yelling, sling-'em-free-buns style (with miniature pop-up features, of course). I particularly liked the picture of Mother Goose in dark glasses and Liz Taylor headscarf signing autographs at the stage door.

Of course, it's all about the potential of storytelling, the fun of variations: very postmodern. Raymond Queneau would have loved it. But the fun is real fun, incredibly nifty and very warm. Though it seems at times that a story is about to spin out of control, it's always reassuringly gentle and, coming back to earth, makes perfect sense. The book never shows off its cleverness, but invites readers to share the excitement of playing with stories. The pop-up architecture isn't imposing  more Fabergé egg than St Paul's Cathedral  but it's beautiful in miniature and genuinely rewarding, with jokes and surprises of a piece with the stories themselves.

 Simon Mason's Moon Pie is published by David Fickling.