Prolific young adult author David A. Poulsen "handles heavy material with sophistication" (Publishers Weekly). The teens in these three novels confront a teacher who denies the Holocaust, the devastation of atomic bombs, and emotional fallout from the Vietnam War. Includes: And Then the Sky Exploded Ninth-grader Christian Deaver learns his great-grandfather was part of the team that built the atomic bombs dropped on Japan in World War II. During a school trip to Japan, he meets a Hiroshima survivor and tries to make amends. But what can one teenager do? Numbers Just when Andy starts to feel like he finally belongs, can he stand up to the person he trusted the most? Old Man Nate takes an unexpected and unwanted trip with his estranged father, only to undergo changes in his perceptions of both himself and his dad, whose participation in the Vietnam War changed him forever.