My students always responded positively to Herman Wouk's The Caine Mutiny, which won the Pulitzer Prize in 1952. Another book I recommend is Stones from the River by Ursula Hegi, which is set in Germany. Although it covers a great time span than just WWII, it does deal with the impact of Nazism on ordinary townspeople; the main character is a woman who is a dwarf.

One of my favorite books about WWII in high school was a series of reports by the great war correspondent Ernie Pyle entitled Brave Men.  Pyle tended to write stories about common soldiers, sailors and airmen, which reflected the everyday war experiences of men who were not concerned about strategic things but how to survive war on a daily basis.  If you want to understand how the war "felt" to the average combatant or support troops, Brave Men is a worthwhile read, and because it was written for the average newspaper reader on the home front, is very accessible for a high school student.

I second an earlier comment that Heller's Catch-22 is a great novel to come out of WWII, arguably the finest.  Even though some of the comedic elements may seem outlandish to readers, Heller captured the absurdity of certain aspects of military life and WWII better than anyone else has done then or since.

Another favorite is a book written by a young Marine, Eugene Sledge, entitled With the Old Breed, about his experiences in the Marine Corps during WWII, and specifically about the war in the Pacific.  Sledge, who was not a professional writer, captures the camaraderie of being in the smallest branch of the services, as well as the horrors of fighting several battles in the Pacific against an enemy that did not seek, or give, any quarter.  Sledge conveys the "cognitive dissonance" of coming from a small American town and being thrown into, at the the age of 17 (I think), some of the most violent battles of WWII.

Stephen Ambrose's books Band of Brothers and Wild Blue Yonder, which follow a paratrooper unit invading Normandy and the Army Air Corps, respectively, would be two very good reads, especially for an AP class.

I will agree that I love Night by Elie Wiesel. It is incredibly moving and honest. I also really enjoyed the Nazi Soldier's Wife because it is a very different perspective on the war. Both of these pieces are nonfiction. 

As far as fiction, I read the young adult novel The Book Thief this summer and it was amazing. The writing is beautiful and the experience of the young German girl who has been profoundly influenced by the holocaust was very engaging. It taught me a lot about the Hitler's Youth and the rules that the Nazis had for Germans. In the novel, the Nazi's rules regarding joining the party affect the main character's adopted father greatly. He loses his business and respect in the community. The story is told from Death's point of view and follows the main character through her life in relation to times she encounters death. Very powerful and accessible for students. 

My students also enjoyed The Boy Who Dared by Bartoletti which is fiction but based on a true story. It tells the story of a boy who stands up against the Hitler Youth and the nazis. It tells the story of how the Third Reich comes to power and how they use propaganda to lie to the Germans and take power.  It is told through flashbacks as the main character is on death row for standing up against the Nazis.

http://www.enotes.com/the-book-thief

http://www.enotes.com/the-boy-who-dared/enotes-synopsis

Two of my favorite books about WWII are Night by Ellie Wiesel and The Hiding Place by Corrie Ten Boom.  Both are non-fiction works that follow the lives of someone experiencing World War II in Europe.  Night follows the story of a young Jewish boy.  He goes through the internment camps and shows many different aspects of life for a Jew during this time period.  Personally, I liked this story a little more than The Diary of Anne Frank because it showed many different aspects of life as a Jew rather than just hiding.  The Hiding Place follows the story of a woman and her family who hide Jews.  They are not Jewish themselves but they do not believe in the Nazi principles.  The book shows a different perspective of life during this time period.  It shows the difficulties of the average citizen and the choices they were faced with.  The family in the story ends up as political prisoners.  There is certainly a point of comparison between the different types of prisoners in the death camps.  This book also covers some of the efforts made to help former prisoners after the war.  

http://www.enotes.com/night-wiesel

http://www.enotes.com/hiding-place

My favorite novel of all time is Joseph Heller's Catch-22. I was lucky enough to first experience it during my senior AP English class in high school, and I'll never forget my teacher for making such a terrific choice. It was 1972, and the Vietnam War was still going on, and it seemed a perfect book to read at the time. Catch-22 is filled with sex and the "F" word, so this may preclude you from teaching it in more conservative schools (or where principals and parents may object), but you'll be hard-pressed to find a better fictional novel with a WWII setting.

A novel often taught in high school is A Separate Peace. This book deals with the effects of WWII on students who are preparing to be called up to fight. Though the novel is set in the US, it does demonstrate the far-reaching impact of the war and brings home the idea that it was children who fought. 

Also this book is at a reading level that works for 10th, 11th, and 12th graders. 

Winston Churchill wrote a six-volume History of World War II which has been read by millions of people. The whole work, of course, would be too much for a high school course. The best volume is the second one, titled Their Finest Hour. it tells how Britain stood alone against the heavy bombing raids and potential invasion after the surrender of France in 1940. Churchill is an excellent writer. He was Prime Minister during most of World War II and writes with great authority. He was a friend of President Franklin D. Roosevelt and met with him many times before and after the Pearl Harbor attack brought America into the war. Their Finest Hour should not be difficult reading for 10th to 12th grade students.

Editors Note:  I tried to move this to the topic World War II, but at the moment it didn't show an independent topic for World War II... only topics like World War II in literature.

Survival in Auschwitz, by Primo Levi, is an excellent choice for upper level high school students to read as part of a study about the holocaust or race relations as a greater part of World War II.

The book is an autobiographical account of Primo Levi, an Italian Jew who was captured and sent to the concentration camp in Auschwitz.  While the book does have some gory details, it successfully describes the horrors of the situation that many Jews faced without giving the book a nightmarish feel.  The account of Levi's year long struggle in Auschwitz against the guards, the elements, and his fellow Jews is a true story of survival that helps bring new perspectives to the reader.  It also talks about events of the war, such as their rescue by the Soviets, that could help foster a more meaningful understanding of key events in the war.

The eNotes link below includes chapter summaries of the book that will provide greater detail when deciding if this book meets the requirements for this particular study of World War II.

One frequently assigned text is The Diary of Anne Frank, the autobiography of a young Jewish girl killed in the Holocaust. It is especially good for this age group because it gives a first person account of the war as seen through the eyes of a victim who was their own age. Kurt Vonnegut's Slaughterhouse Five is also a potentially good text.