Age: Middle School & advanced readers
History: World War II
Music: Harmonica, Piano, Flute

Multiple storylines: check. Inclusion of music: double check. Continuity of one object across multiple story lines: checkity check check. All my favorite things, all in one book.

As the story revolves around a distinctly unique harmonica, I would highly recommend this as an audiobook due to its periodic inclusion of harmonica riffs and actual songs. Plus, there are multiple narrators throughout (based on each story) and some excellent German accents. Without much gore or violence and with no romance, this would make a perfect car trip audiobook for grades 4+.