This fourth-grade curriculum guide, designed as part of a K-12 program to strengthen understanding of the American heritage, introduces the formal study of American history through biographies which reveal how various American peoples lived and how together they shaped a distinctively American way of life. The five "key ideas" of the study are arranged chronologically: (1) how the Americans were discovered and explored, (2) how different cultural and ethnic groups settled and developed colonies in North America, (3) how the United States of America was established, (4) how our nation was developed through the conquest of the West and the Civil War (to 1900), and (5) how we have been and are being led into the Great Society. Content outlines for the key ideas, songs, maps, sea charts, stories, numerous learning activities, and lists of related books, filmstrips, and transparencies are provided in the guide. (JB)