Barely two centuries ago, most of the world's productive land still belonged either communally to traditional societies or to the higher powers of monarch or ch

Harvard’s acclaimed geologist “charts Earth’s history in accessible style” (AP) “A sublime chronicle of our planet." –Booklist, STARRED review How w

(Ages 9-12) You are a young Orcan living on Planet Orca, where curiosity and exploration are punishable by exile. You are fascinated by your planet's secret off

In 1790, America was in enormous debt, having depleted what little money and supplies the country had during its victorious fight for independence. Before the n

"I take care of the earth because I know I can do little things every day to make a BIG difference..." With his signature blend of playfulness and sensitiviy, T