@johnd13: No problem

Enders Game quartet by Orson Scott Card

Summary:

It's 2070, forty years since a devastating alien invasion was barely turned back, and the world is desperately searching for soldiers to lead them to victory when the "Buggers" come again. That's why they're drafting young children who pass a rigorous screening, and sending the best of them to the orbiting Battle School, where they are trained from childhood to be ready for war in the vertiginous reaches of space.

Into the unending pressure of military training comes six-year-old Andrew "Ender" Wiggin, who struggles to keep his humanity even as the adult teachers, rivals among his fellow students, and the strange unseen influence of the alien invaders all threaten either to destroy him or to make him into someone he can't bear to be.

His genius raises him to the top of the intensely competitive games in the Battle Room, an immense null-gravity chamber where armies of youngsters engage in mock combat. But his real struggles are off the playing field - with a dangerous older boy named Bonzo Madrid who is determined that both he and Ender cannot survive in this place; with his teacher, Mazer Rackham, who won the last war on a fluke and now is trying to prepare Ender to win the next one by skill rather than luck; and with himself, as Ender wrestles with his own demons, desperate to remain a decent human being even as he sees himself being transformed into exactly the same kind of monster as the buggers themselves.

Reviews:

Publishers Weekly: For the 20th anniversary of Card's Hugo and Nebula Award–winning novel, Audio Renaissance brings to life the story of child genius Ender Wiggin, who must save the world from malevolent alien "buggers." In his afterword, Card declares, "The ideal presentation of any book of mine is to have excellent actors perform it in audio-only format," and he gets his wish. Much of the story is internal dialogue, and each narrator reads the sections told from the point of view of a particular character, rather than taking on a part as if it were a play. Card's phenomenal emotional depth comes through in the quiet, carefully paced speech of each performer. No narrator tries overmuch to create separate character voices, though each is clearly discernible, and the understated delivery will draw in listeners. In particular, Rudnicki, with his lulling, sonorous voice, does a fine job articulating Ender's inner struggle between the kind, peaceful boy he wants to be and the savage, violent actions he is frequently forced to take. This is a wonderful way to experience Card's best-known and most celebrated work, both for longtime fans and for newcomers.\

School Library Journal: This new young adult edition of the Hugo and Nebula Award-winning classic sci-fi novel by Orson Scott Card, winner of the Margaret A. Edwards Award for outstanding lifetime contribution to writing for teens, includes an original postscript by the author in which he discusses the origins of the novel is all about leadership. The novel asks: What does it take to successfully lead men into battle? The buggers have invaded Earth twice. The last time mankind survived only because of the brilliance of Mazer Rackham, commander of the International Fleet. Years later, a third invasion is feared and a new commander is sought. Ender Wiggin is only six years old when he is plucked to succeed Rackham and sent to the space station Battle School. He is isolated, ridiculed, bullied, and persecuted—but he survives and thrives. Using his astonishing intelligence, the boy learns to be a top-notch solider and, despite his youth and small stature, is quickly promoted up the ranks. By the age of 12, Ender learns the art of command and earns the respect and fear of his fellow soldiers. This audio version was created in celebration of the 20th anniversary of the novel and it's a gem. The audiobook is narrated by a full cast. Stefan Rudniki is particularly good as Ender. Despite Ender's age, this is not a children's novel. Its profound themes (and mild profanity) call for intelligent teens who appreciate a complex novel.—Tricia Melgaard, Centennial Middle School, Broken Arrow, OK

The Roar (My Personal Favorite) by Emma Clayton

Summary:

The Roar takes place in a "post-apocalyptic" world where a disease known as the "Animal Plague" infects every animal and causes them to turn vicious and attack humans. Of what they have been told.

When the plague began the entire population came together and built a solid concrete wall 50 feet high and 30 feet thick. On the top of the entire wall there is an electrified fence and invincible, laser hurling Ghengis borgs mounted every few yards.Behind this wall the population that survived has been living for more than 30 years. Many things have come about since space is limited. The government created a law that forbade people to have children. The Northern Hemisphere is where the population has gone to survive with all the melons. Outside of "The Wall" the majority of the population has been made to believe that it is covered in a yellow poisonous dust that was used to kill all living things, because of the plague.

Reviews:

"A hugely inventive and entertaining read which grabs the reader by the scruff of the neck from the first sentence. It flies along like a laser beam from a blaster and sustains the breakneck pace until the stunning climax. A fresh and exciting take on sci-fi..." -- Eoin Colfer

“Telepathically connected twins battle a totalitarian regime…Exciting, thought-provoking, and very hard to put down.” – The New York Times Book Review

“An exciting, suspenseful plot; this compulsive read should not be started at bedtime!”

– Kirkus Reviews

“An unusually gripping adventure…roars to a satisfying conclusion.”

– BCCB

Humanity's Fire series by Michael Cobley (Summary and reviews taken from the first book in the series called "Seeds of Earth")

Summary:

The first intelligent species to encounter mankind attacked without warning. Merciless. Relentless. Unstoppable. With little hope of halting the invasion, Earth’s last roll of the dice was to dispatch three colony ships, seeds of Earth, to different parts of the galaxy. The human race would live on … somewhere.

150 years later, the planet Darien hosts a thriving human settlement, which enjoys a peaceful relationship with an indigenous race, the scholarly Uvovo. But there are secrets buried on Darien’s forest moon. Secrets that go back to an apocalyptic battle fought between ancient races at the dawn of galactic civilisation. Unknown to its colonists Darien is about to become the focus of an intergalactic power struggle, where the true stakes are beyond their comprehension. And what choices will the Uvovo make when their true nature is revealed and the skies grow dark with the enemy?

Reviews:

“…a convincing portrayal of political machinations and the plight of individuals caught up in events beyond their comprehension.” – Eric Brown for The Guardian

“…this is the sort of thing that Space Opera readers love. We’ve got spaceships and a broad history, shown through the viewpoints of multi-person perspectives, linked together in a way that Heinlein would’ve been proud of.” – Mark Yon for SFFWorld.com

“…a compelling and impressive book, and one that I really enjoyed.” – Simon Appleby forBookgeeks.co.uk

“Cobley has a strong confident voice with a intriguing and different tale to tell.” – Gav, forNextRead.co.uk

Edit-- Also yeah read Eric Nylund's Halo books especially Fall of Reach which is the best one I have read from him.