A look inside Richard Feynman’s calculus notebook

One of the most unusual artifacts at the Niels Bohr Library & Archives in College Park, Maryland, is a small green notebook once owned by Richard Feynman. It contains handwritten notes he compiled as a high school student in the early 1930s, on a book called Calculus for the Practical Man. We usually think of Feynman as an impish twenty-something prodigy at Los Alamos or as the celebrated Caltech professor who enthralled undergraduates with his lectures and stories. But Feynman was once a teenager—and not even he was born knowing calculus.