The Legend series by Marie Lu:
From very different worlds, June and Day have no reason to cross paths - until the day June's brother, Metias, is murdered and Day becomes the prime suspect. Caught in the ultimate game of cat and mouse, Day is in a race for his family's survival, while June seeks to avenge Metias's death. But in a shocking turn of events, the two uncover the truth of what has really brought them together, and the sinister lengths their country will go to keep its secrets.
The Pact by Jodi Picoult
For eighteen years the Hartes and the Golds have lived next door to each other, sharing everything from Chinese food to chicken pox to carpool duty-- they've grown so close it seems they have always been a part of each other's lives. Parents and children alike have been best friends, so it's no surprise that in high school Chris and Emily's friendship blossoms into something more. They've been soul mates since they were born.
World War Z by Max Brooks
The Zombie War came unthinkably close to eradicating humanity. Max Brooks, driven by the urgency of preserving the acid-etched first-hand experiences of the survivors from those apocalyptic years, traveled across the United States of America and throughout the world, from decimated cities that once teemed with upwards of thirty million souls to the most remote and inhospitable areas of the planet.
If I Stay by Gayle Forman
Choices. Seventeen-year-old Mia is faced with some tough ones: Stay true to her first love—music—even if it means losing her boyfriend and leaving her family and friends behind?
Then one February morning Mia goes for a drive with her family, and in an instant, everything changes. Suddenly, all the choices are gone, except one. And it's the only one that matters.