Harry Thomas, 13, of Fort Worth, Texas, above, makes his entrance at the Southern Cultural Heritage Center Wednesday evening to participate in a debate on the pros and cons of pre-Civil War slavery. The 85 students in the school’s seventh grade at Fort Worth Country Day School are spending four days in Vicksburg visiting the city’s historic places. Similar trips have been made by the school over the past several years. At right, the debate teams face off on the stage of the former St. Francis Xavier Academy auditorium.