The Hunger Games, Catching Fire, and MockingJay by Suzanne Collins.

Synopsis (for book one only, as the synopses for later books contain spoilers for book one):

In the ruins of a place once known as North America lies the nation of Panem, a shining Capitol surrounded by twelve outlying districts. Long ago the districts waged war on the Capitol and were defeated. As part of the surrender terms, each district agreed to send one boy and one girl to appear in an annual televised event called, "The...