Funnily enough, I'm answering this question in my childhood bedroom, in the house where I was born, where my three big sisters taught me to read, playing at schools every day (I can't remember not being able to read; certainly I was well away by the time I got into my first real classroom with a non-sister teacher).
And in the bedside cabinet is ... pause to look ... Five Go To Smuggler's Top by Enid Blyton (1945).
I must have read it a fair few times, along with the other stories in the Famous Five series. In each one, a group of cousins (four of them) come home from boarding school for the summer, shake off the grown-ups (Uncle Quentin and Aunt Fanny) and disappear off with their dog (the fifth one) on a hike, in a caravan, after a circus, to a treasure island . . . there to be posh, solve crimes and eat picnics. Hogwarts food was pretty much Famous Five food and Scooby-Doo will give you an idea of the plotting.
Much, much better than these though was Ballet for Drina by Jean Estoril (1957) and five of its ten sequels. No, wait - hear me out. Okay, Drina is an awkward little shrimp of a girl, orphaned, living with her grandparents, who blags her way - Billy Elliot style - into ballet classes and, predictably, becomes a ballerina. But besides the clichés, there are friendships, passions, secrets, betrayals, concern for social justice, wrongs righted, triumphs, disappointments and some the best Mean Girls ever.
As well as all that, once Drina knows her arabesques from her elbows, she starts to tour with the corps de ballet and, an intrepid Londoner, she takes Paris and New York in her plucky but dainty stride. Then she goes to the Edinburgh Festival. That story was my first experience of reading a book set in a place I knew - having resisted Walter Scott and being too young for Jekyll and Hyde - and the detail was enchanting. I had been on those streets and looked at those views. It made me want to see how accurately Estoril had depicted London, Paris and New York too.
Luckily, it didn't make me want to be a ballerina. I was five foot eight at the age of twelve and could trip over the pattern in the carpet. But the reason I can't take a quick phone picture of Ballet For Drina is that it's not here; all six books are in my house in California in the glass-fronted bookcases where the treasures stay. I've read them many times and I still reach for them when life gets the way life does. If anyone else has read them - sssshhh! (There's a massive plot twist at the end of book 1) - but let me know if you too love them.