Throughout his life, Benjamin Banneker was known and admired for his work in science, mathematics, and astronomy, just to name a few pursuits. But even when he was born in Maryland in 1731, he was already an extraordinary person for that time period. He was born free at a time in America when most African Americans were slaves. Though he only briefly attended school and was largely self-taught, at a young age Benjamin displayed a keen aptitude for mathematics and science. Inspired by a pocket watch he had seen, at the age of 22 he built a strike clock based on his own drawings and using a pocket-knife. This picture book biography focuses on one episode in a remarkable life.