Okay, so general consensus that I've read say that this book is like a sci-fi Harry Potter. However, it's only half HP...the other half is Ender's Game. It's like Ender and Harry had a lovechild. Sort of. This is it.
I gave Ender's Game and the majority of the HP series 5 stars. This, I give 4, because although I enjoyed it, it was like a bit of a lesser HP, and a bit of a lesser Ender. This book also was written with the specific purpose of continuing the story in "The Million Year Journey." In essence, this book shouldn't be read as a standalone. I would say the closest comparison would be The Empire Strikes Back...big drama, good guys are somewhat defeated, etc.
So I'll break it down a bit more, without giving spoilers.
HP similarities:
1. Young kid (12 years old I think) has a bad family life, goes to a special school where they're taught non-mundane skills
2. The popular school game is played in space ships, but is closest in gameplay to Quiddich.
3. Kids normally go home for holidays and summers, but Fintan of course doesn't want to go home.
4. A lot of the story is about Fintan's daily life, classes/learning, and finding his place in the school
5. School "squadrons" split into 4 groups (should have just named them Ravenclaw, Hufflepuff, Slytherin, and Gryffindor, lol)
Ender similarities:
1. Young kid is super smart (details of why found out in the book), chosen as "the One" by the leaders, whatever that means.
2. The leaders have a brief back-and-forth discussion of the progression of the main character at the beginning of each chapter
3. The popular school game is played in space ships rather than space suits in zero gravity, but the game strategy teaches the kids a skill they'll need in the "real" world.
4. Sure there's other good comparisons, but I'm getting bored of this.
So anyway, the story is good. The second book should flesh out the first and give the story a bit more of a finale. The ending was just too abrupt. Moving on to "The Million Year Journey" now.