Prisoner B-3087 by Alan Gratz

When this historical novel begins, it is 1939 in Krakow, Poland.  Yanek Gruener is ten years old living with his loving mother and father in a nice apartment on the second floor of an apartment building.  The apartment is quite spacious for the three of them.  Imagine the conditions in the apartment when four other families (a total of sixteen people) are forced to live in the same space!  That is exactly what happens when Hitler’s army invades Poland and turns the area into a Jewish ghetto.

Despite the deplorable conditions of the Jewish ghetto, nothing could prepare Yanek for what was to come once the ghetto was liquidated. Liquidated means once all the people are sent out of the ghetto either to their deaths or to a death camp.

Yanek’s strong will to live, to survive the death camps- ten in all before the war ended in 1945- is a testament to the spirit. The title of the book has to do with the number that is tattoed onto Yanek's arm by the Nazis.

If you like to read historical fiction, this is an excellent choice! 
The reason it is such a powerful book is it is based on the survival of Jack Gruener who currently lives in Brooklyn, New York.