Gladys's mind swirls with numbers and shapes as the world enters the high-tech space age. This is the lyrical true story of a groundbreaking Black mathematician whose inventions led to the creation of GPS. Little Gladys is a farm girl who loves math. But as a Black kid growing up in Virginia in the mid-twentieth century, she sees life around her as less than or greater than but never equal. When a teacher calls her "college material," Gladys knows she can achieve her dreams--and goes on to get a higher education and land a job calculating trajectories and orbits at a naval base with only four Black employees. To help space rockets land safely, Gladys uses satellites to create a better model of Earth, which looks more like a lumpy potato from Gladys's childhood than a perfect sphere! Gladys's amazing work eventually leads to the creation of GPS, which now lets people everywhere navigate our uneven planet. Effervescent illustrations enhance the true story of this remarkable woman who paved the way for future thinkers and innovators. Back matter includes a biography, timeline, author's note, references, and even a section on lumpy potato science!.