Girls have always excelled in subjects that are artistic or literary while boys have traditionally worked better with numbers, formulas and algorithms. Right? Wrong. Science was originally considered a "girl's subject" in the early nineteenth century, with a greater percentage of girls' schools offering equally sophisticated courses in physics, astronomy and chemistry than did comparable institutions for boys. This insightful study provides a comparative analysis of the history of science education for adolescent boys and girls. Tracing the evolution of girls' scientific interests from the antebellum era through the twentieth century, it expands the understanding of the obstacles that emerged to change the dominant gender in science studies.