What is the name of this movie? I think I saw it around 10 yrs. ago.?

A husband, wife, and approx. eight year old son are taken to a Nazi concentration camp to be sorted. The husband smuggles the son into the men's camp and hides him in the barracks, because it's his best bet for keeping the child alive. He tells his son that this is all one big reality-ish game and that the prize is a ride in an American tank. Dad does a good enough job to keep the kid fooled til the Americans liberate the camp. Can't remember exactly how it ends, but the dad is killed and the kid gets to ride in an American tank.