Students from Murphy will transfer to Clark Shaw Magnet School when classes resume after the holidays.
Murphy's enrollment is about 2,000 students, and Clark Shaw already has 750 students. But officials say it can accommodate more than 1,200 students, and 50 trailers will be brought in for use as portable classrooms.
Mobile school superintendent Martha Peek says students from Clark Shaw will return to school as normal after the break, and Murphy students will begin the following week on a staggered schedule.
Damage to Murphy High is being estimated at as much as $10 million. The school dates to the 1920s and was once Alabama's largest.