What Stars Are Made Of

In this assured debut, science whiz Libby Monroe shines when she selects Cecilia Payne, an astronomer who first determined the composition of stars, for an American History profile of someone excluded from the textbook. Like the author, 12-year-old Libby has Turner Syndrome, which means she has a single X chromosome, her heart is “three sizes too big,” and she looks different from her classmates. Libby’s intellectual curiosity already makes her stand out from her peers, but some elements of her condition, such as the fact that she wears hearing aids, make forming friendships difficult. She considers the library her best friend, until new girl Talia Latu moves to Colorado. Allen deftly sketches the dynamics of Libby’s close-knit family, conveying Libby’s anxiety when her older sister Nonny’s pregnancy develops complications. To solve Nonny’s financial problems, Libby dreams of winning the Smithsonian Women in STEM contest, which offers a cash award. Though a thread about Libby’s contacting the textbook’s editor feels tangential, it offers comedy and a lesson in disappointment and persistence. This witty novel’s heroine proves winning, whether or not she gains top prize. Ages 10–14. (Mar.)