A student steps off a school bus in Lamar, S.C., in 1970 as a National Guardsman looks on. The widespread adoption of forced busing for desegregation during the 1970s sparked protests and even violence in some communities. --Corbis Bettmann

Like a sharp knife slicing through the heart of 20th-century America, Brown v. Board of Education of Topeka divides education in the past 100 years into two distinct eras. The decades before the U.S. Supreme Court's historic 1954 ruling saw the creation and tenacious defense of a system of racial separation in public schools throughout the South.

That system, along with widespread but less formal segregation elsewhere, relegated millions of black children to an inferior education. The years since the Brown decision record the often-bitter struggles to end segregation and to ensure a good public education for children of all races.

The third installment of "Lessons of a Century," a yearlong Education Week series of monthly special sections, looks at public school desegregation. Included are an examination of the pivotal court cases, a look at a Virginia district where deep division has given way to a surprisingly integrated system, and special "Perspective" essays. (Read parts one and two).

Visit the "History of Education," an initiative of Henk van Setten, associate professor at the university of Nijmegen, Netherlands. The index lists topics ranging from important educators pre-1750 to post-1900. Also included are links to select U.S. education history sites by state (scroll down to find these).