Long before calculators were invented, little Edith Clarke devoured numbers, conquered calculations, cracked puzzles, and breezed through brainteasers. Edith wanted to be an engineer-to use the numbers she saw all around her to help build America. When she grew up, no one would hire a woman engineer. But that didn't stop Edith from following her passion and putting her lightning-quick mind to the problem of electricity. But the calculations took so long! Always curious, Edith couldn't help thinking of better ways to do things. She constructed a "calculator" from paper that was ten times faster than doing all that math by hand! Her invention won her a job, making her the first woman electrical engineer in America. And because Edith shared her knowledge with others, her calculator helped electrify America, bringing telephones and light across the nation.