Thomas and Tamara are track stars at their rural New Mexico high school. Like many teenagers, they are torn between the lure of brighter futures elsewhere and the ties that bind them to home. For these teens, however, home is an impoverished town on the Navajo reservation, and leaving means separating from family, tradition and the land that has been theirs for generations. Erica Scharf's "Up Heartbreak Hill" is a look at a new generation of Americans struggling to be both Native and modern.