Have your student pick from the various classic apocalyptic novels. Some of our story is drawn from these books, but it won't ruin, nor particularly gain anything from the books to influence the scenario. The goal is to immerse them in the beginning of the genre and give the student some things to think about.
The Last Man, Mary Shelley Written by the same author as Frankenstein, this book is often called the first of the apocalyptic genre. It is also often considered a tribute to Lord Byron, who had died when he became ill during a military expedition and Percy Shelley, who drowned in a storm in a schooner. The novel's first 200 or so pages describe in the Romantic era tradition the ups and downs of the lives of the main characters, which follow many of the things that happened in Byron's and Percy Shelley's lives through romantic-era goggles. It has many passages for thought, however, as the last man on earth thinks about life and mankind. Because it is a difficult read for the modern audience, I would save this just for high school students.
Brave New World, Aldous Huxley or 1984, George Orwell Both of these novels are not apocalyptic in the sense of zombies and the like, but speak to the political end-of the world. Both appropriate for high school students. 1984 is of a middle school reading level, so a mature middle school student could read it.
The Island of Dr. Moreau, H.G. Wells This novel is the narration from Edward Prendick, who became shipwrecked and is left on the island of Dr. Moreau by a passing boat. Prendick discovers that Dr Moreau is creating Human-Animal hybrids by vivisection. Lots of discussion on ethics and morality can come from reading this book.
Animal Farm, George Orwell Although allegorical, the book does bring up the issues of the differences between man and beast and our responsibilities as ethical men.
The Machine Stops, Graham Greene A short story that addresses the issues of man's connection to the natural world.
I am Legend, Richard Matheson Considered the book that inspired the development of the zombie-vampire genre of fiction. Influential in popularizing the concept of a worldwide apocalypse due to disease. Was adapted into several movies.