Wangari Maathai was born in Nyeri, Kenya, in 1940 and became the first woman in East and Central Africa to earn a doctorate. In 1976, while serving with the National Council of Women of Kenya, she introduced a simple idea: plant trees with ordinary people. That idea grew into the Green Belt Movement, a grassroots effort that helped women plant more than 20 million trees on their farms and on school and church grounds. It spread to other African countries too, as people she trained started their own tree-planting efforts. In 2004 she received the Nobel Peace Prize. It didn’t start with a grand plan to change a continent. It started with a seedling and a willing pair of hands, and then another, and another.