Both Number the Stars and "The Boy in the Striped Pajamas" explore themes of friendship, deception, and confinement from a child's perspective during the Holocaust. Friendship transcends differences, as seen with Annemarie and Ellen, and Bruno and Shmuel. Deception plays a role in survival and protecting innocence, though it leads to different outcomes. Confinement highlights feelings of claustrophobia and helplessness, as characters are trapped by their circumstances and forced to hide or stay in unwanted places.

The theme of "Number the Stars" centers on bravery, both individual and collective. Annemarie's character development showcases her growing courage as she helps her Jewish friend Ellen escape Nazi persecution, despite the dangers involved. The story also highlights the collective bravery of the Danish people, who risk their lives to protect Jews. This includes actions like Uncle Henrik using his fishing boat to aid in their escape, emphasizing the moral imperative to do what is right.

This quote helps Annemarie to come to a deeper understanding of what bravery is.