The nation's top education official says she's impressed with developments in what was once one of South Carolina's most underperforming school districts.

U.S. Secretary of Education Betsy DeVos spoke Thursday after touring schools in a district that's one of several dozen along Interstate 95 bestowed with the nickname "Corridor of Shame" because of their substandard schools.

DeVos said she was encouraged to see improvements like a more diverse curriculum that have come since last year, when state Superintendent of Education Molly Spearman declared a state of emergency in Florence School District Four and took over its management. By sharing some services with neighboring districts, state officials say they've saved more than $600,000 in the struggling district's budget.

The visit comes amid ongoing debate on how to improve South Carolina's education system.