I first read this book when I was 10, and it pretty much blew my mind. I used to reread it at least once a year throughout my adolescence, and I recently revisited it. It still holds up as an excellently written novel - tightly plotted, with amazing character development (despite an overwhelmingly large cast, every single character changes by the end of the novel). I love how Raskin masters the art of misdirection, and her wordplay is extremely clever. Almost twelve years after I first read the novel, I sat there today marveling over how Raskin sets up tension by the end of the first chapter (Who were these people, these specially selected tenants? They were mothers and fathers and children. A dressmaker, a secretary, an inventor, a doctor, a judge. And, oh yes, one was a bookie, one was a burglar, one was a bomber, and one was a mistake.). 
 Turtle remains one of my favorite literary heroines, even if she's not one that gets name-dropped very often, but grown-up me finds herself loving characters like Josie-Jo Ford and Angela. Highly recommended.