Terrible Things: An Allegory of the Holocaust – Eve Bunting – age 6+
Hiding from the Nazis – David Adler – true story – age 7+
A Hero and the Holocaust: The Story of Janusz Korczak and His Children – David Adler – Gr. 2+
Anne Frank: Life in Hiding – Johanna Hurwitz – ages 9+
Raoul Wallenburg: The Man Who Stopped Death – saved Jewish lives-Sharon Linnea-ages 9+
Raoul Wallenberg : Swedish diplomat and humanitarian -Thomas Streissguth – gr. 7+
Raoul Wallenburg: Rescuing Thousands From the Nazi's Grasp – ages 9+ - Debra McArthur
Remember Not to Forget: A Memory of the Holocaust – introduction to Holocaust- Norman Finkelstein – age 6+
Passage to Freedom: The Sugihara Story – Jews saved to Japan- Ken Mochzuki-gr. 2-5
Number the Stars – Denmark Nazi Resistance- Lois Lowry – ages 8-12
The Hidden Children- Howard Greenfield-ages 8-12
Ten Thousand Children: True Stories Told by Children Who Escaped the Holocaust on the Kindertransport- Anne Fox – gr. 4-8
The Endless Steppe – Esther Hautzig – ages 10+
When he's older, at least grade 5:
Hitler Youth: Growing Up in Hitler's Shadow - Susan Bartoletti
Surviving Hitler: A Boy in the Nazi Death Camps – Andrea Warren – ages, for a mature 10+ The Devil's Arithmetic - Jane Yolan - age 10+
Also:
The TUskegee Airmen Story: http://www.amazon.com/Tuskegee-Airmen-Story-Lynn-Homan/dp/1589800052/ref=pd_sim_b_9
The Tuskegee Airmen (We the People Series): http://www.amazon.com/The-Tuskegee-Airmen-We-People/dp/0756514045/ref=pd_sim_b_1
Tuskegee Airmen - Cornerstones of Freedom series
Baseball Saved Us: http://www.amazon.com/Baseball-Saved-Us-Ken-Mochizuki/dp/1880000199/ref=sr_1_sc_1?s=books&ie=UTF8&qid=1344815657&sr=1-1-spell&keywords=japanese+basweball+saved+us
The Story of Winston Churchill – Alida Sims Markus
If his reading level is good, these Landmark books:
The Battle of Britain by Reynolds
The Rise and Fall of Adolph Hitler by Shirer
Commandos of WWII by Carter
Winston Churchill by Reynolds
Great American Fighter Pilots of World War II by Loomis
The Seabees of World War II by Castillo
Combat Nurses of World War II by Blassingame
Medical Corps Heroes of WWII by Blassingame
The U.S. Frogmen of World War II by Blassingame
From Pearl Harbor to Okinawa by Bliven
Midway: Battle for the Pacific by Castillo
The Story of D-Day by Bliven
Battle of the Bulge by Toland
From Casablanca to Berlin by Bliven
The Battle for Iwo Jima by Leckie
Thirty Seconds over Tokyo by Lawson
Ben Gurion and the Birth of Israel by Coway
The Childhood of Famous Americans Series:
Douglass MacArthur
Franklin Roosevelt
George S. Patton
Albert Einstein
Harry S. Truman (Roosevelt's VP)
Dwight D. Eisenhower
Also, my son enjoyed the DK Eyewitness, too. I second (or third?) Winged Watchmen.
The Focus on the Family's Story of Deitrich Bonhoeffer is excellent.
The movie Tora, Tora, Tora is great. My children were around ten when they watched it, so preview. But no sex and I don't recall language, maybe one here or there.
Of course, John Wayne movies!
I encourage you to encourage him to also learn about WW I; without it and the political aftermath, it's possible WW II wouldn't have happened and a man like Hitler would not have been able to put his spell over such a sophisticated country as Germany.
First Book of the Long Armistice- Louis Snyder
Russell Freedman- The War to End all Wars:
http://www.amazon.com/The-War-End-All-Wars/dp/0547026862/ref=la_B001ILIEB2_1_6?ie=UTF8&qid=1344814604&sr=1-6
and
Truce:
http://www.amazon.com/Truce-The-Soldiers-Stopped-Fighting/dp/0545130492/ref=pd_sim_b_7
If I ever find it for $35, I'll buy it for myself as an extra copy. It's worth every penny of whatever you have to pay. I got mine in unread condition for $55 and was thrilled to find it for that.