This was a fun book for tweens that I appreciated, although I'm much older than that age. :) Shulman moves from fairy tales The Grimm Legacy to science fiction novels with this book, but it still takes place in the New York Circulating Material Repository. Leo is the least scientifically-gifted in a family full of science geniuses. But he gets the opportunity to explore science in a way that his siblings never had. He'll find out for himself that time machines are real, among other really cool devices.
I thought this was pretty cute. I liked Leo's characterization. He was adorable with and his floppy black curl on his forehead. His crush on Jaya was very cute. Jaya seemed very mature for her age, which was interesting. I like that it's no big deal that he's Russian American and she's Indian American (not Native but the country). The use of various science fiction novels in the story was a fun touch. I mean, that would rock to be able to use The Time Machine and to meet Nicola Tesla.
Also, the use of Nicola Tesla was an interesting touch. I learned some new things about his conflict-ridden relationship with Thomas Edison and about Lewis Latimer, who was a black man whose work with electricity went a long way towards Edison inventing the light bulb. He actually drafted the patent for the telephone with Alexander Graham Bell before his work with Edison.
I'm always a fan of metafiction, and I liked that idea that devices from classic science fiction novels really worked in this book. Don't expect technical explanations that would stand up under rigorous scientific scrutiny. It's a major suspend disbelief in some aspects, but that's what fiction is often about.
I only gave this three stars because I felt like some parts of the story was lightweight. I would have preferred a little more story development in some areas. I think the ending wraps up a little too neatly. But I still enjoyed listening to this, narrated by the excellent Johnny Heller.