This U.S. history curriculum guide, based upon the historical essays written by Richard B. Bernstein, is intended for students in grades 9 - 12 and refines and extends the understanding of U.S. history that students have acquired to date. Students are challenged to venture into historical explorations and analyses in order to compare and contrast historians' changing explanations of the past, and to engage in the various forms of historical data and evidence. The guide is divided into twelve units: (1) "A World of Their Own: The Americas to 1500"; (2) "Contact: Europe and America Meet, 1492-1620"; (3) "The Founding of New Societies, 1607-1763"; (4) "What Was the American Revolution? 1760-1836"; (5) "The Ambiguous Democracy, 1800-1848"; (6) "'Now We Are Engaged in a Great Civil War,' 1848-1880"; (7) "'What, Then, is This American?' 1865-1900"; (8) "Waves of Reform, 1880-1921"; (9) "Boom and Bust, 1921-1933"; (10) "The Age of Franklin D. Roosevelt, 1933-1945"; (11) "Leader of the Free World, 1945-1975"; and (12) "A Nation in Quandary, 1975--." Each unit is comprised of the content to be covered, a teacher's rationale, a table of contents, and detailed lessons and activities. (LB)