Wendy Lichtman writes personal essays for the Washington Post, New York Times, San Francisco Chronicle, and Good Housekeeping, among other national publications. She has also written four previous young adult novels, including Do the Math: Secrets, Lies, and Algebra. She holds a degree in mathematics and has tutored public-school students in algebra for several years. When she decided to write about a teenage girl who realizes that some questions have more than one right answer, algebra, with its unknowns and variables, seemed a perfect metaphor. Wendy Lichtman lives in Berkeley, California.