Electricity was restored to Atholton High School Wednesday afternoon, and the Columbia school will open its doors to students and staff on Thursday.
Atholton is the last public school in the county to open after Hurricane Irene forced the cancellation of the first day of classes Monday, Aug. 29.
Most county schools opened Tuesday. Those that did not were Atholton, Glenelg and Marriotts Ridge high schools; Dunloggin, Folly Quarter and Mount View middle schools; and Northfield, St. John's Lane, Triadelphia Ridge and West Friendship elementaries.
The only school without electricity Wednesday was Atholton, located on Freetown Road.
The weekend storm left water damage in nearly half of the system's 73 schools, according to a statement, but officials said the clean-up was completed by Tuesday.
The school system also announced Monday that athletic practices would be held at all high schools, even if a school was closed.
"We have games scheduled for Friday," said athletics coordinator Mike Williams, in a statement, "so we want to make sure all teams have adequate and equitable practice time."
Meanwhile, Baltimore Gas and Electric Co. has restored power to 40,025 customers in the county, according to the utility company's website Wednesday evening. Another 6,534 customers still are without power.