Ender's Game is about Ender Wiggin, the third child in his family. In this future, Earth is becoming overpopulated and in an effort to conserve resources, families are limited to two children. Adding insult to injury, Earth was attacked by the "buggers", an insectoid race bent on annihilating the human race. Due to the unique nature of the Wiggin family, they are authorized a third child in hopes that he will be able to combat the "bugger" threat.
The book follows Ender as he heads to attend the Battle School, a special school in Earth orbit used to train the new generation of leaders for the military. During his time there, Ender faces steep odds and almost insurmountable challenges, all in an effort to shape him to one day lead Earth to victory. All along the way, they'll push him as far as they can without breaking him, running the risk that if they do, humanity is doomed.
If you've been considering picking up the book before the movie releases in November, do it. I think you'll find it a pretty good read, and you'll want to see Ender's Game even more once it releases.
Ender's Game (Kindle Version)
Ender's Game (Print Version)
Till next time, peace!