Sophie Germain grew up France at a time of chaos during the French Revolution. She found order in math. Nothing could detract from her interest, despite mathematics being considered unsuitable for a girl. Sophie thought math was like a poem, and she wanted to write poetry of her own. No university would let her enroll as a woman, so she submitted work under a man’s name. When her identity was finally discovered, she was considered more curiosity than scholar. For years, she studied on her own, eventually solving a problem many considered unsolvable: develop a mathematical formula to predict patterns of vibration. This picture-book account of Sophie’s accomplishment is followed by more about Sophie and her work, including the relationship between math and physics, as well as informative notes from both author and illustrator on their research and approach to this treatment, including how they conjectured about what isn’t known. (Ages 6–9)