One of the books that Liesel read to Max when he was sick is actually the novel "The Book Thief", namely the sentence: "what came to her then was the dustiness of the floor, the feeling that her clothes were more next to her than on her, and the sudden realization that this would all be for nothing".
When first arriving at the school, Liesel sees a large poster with many faces depicting the "ideal" Aryan phenotype for the various the regions. The original was painted by two race obsessed artists, and these posters were placed in every German school, and students were forced to memorize them.
Emily Watson decided to stay in character all day, and in between takes she was still acting as Rosa the grumpy German adoptive mother. It caused her to get into a fight at the airport check-in, when she reacted like her character would do, which caused her some problems.
Liesel's book theft is explored more in the book. Ilsa Hermann, the Mayor's wife, tries to catch them doing it. A deleted scene does have Liesel and Rudy stealing a book with her watching them.
The first time since 2005 that John Williams wrote the music for a film not directed by Steven Spielberg.