(Covers information from Anderson's universe)
Charles Ashford's daughter, Angela Ashford attended the school prior to the outbreak. When the virus began to sweep across the city, Umbrella agents were sent to get Angela out of the city, but the SUV she was in was hit by a truck. Angela was the only survivor of the crash and headed back to the school to hide from the growing number of undead.
At some point and time, the Raccoon City Police Department were sent in to either neutralize the undead or protect the civilians still at the school. Their efforts were presumably in vain, as no survivors besides Angela are ever encountered inside the school; the dogs found inside the building were undead, searching for live prey. The school's undead were primarily school children and the school facility (teachers, janitors and cooks).
At the behest of Dr. Ashford, Jill Valentine, L.J. and Terri Morales entered the school to find Angela. Terri was killed by a group of young zombie children when she mistakes a girl for Angela; Jill manages to locate Angela and the two befriend each other. Nicholai Ginovaef was later killed in an attempt to help Jill and Angela escape.
After Janus Prospero rescues the two from the dogs, they reunite with L.J. and encounter Carlos Olivera; after ascertaining the location of the final evacuation site from Dr. Ashford, the remaining group head for City Hall.
The entire building, along with the rest of Raccoon City was destroyed when Umbrella dropped a nuclear missile in the center of town to cover their tracks by destroying all the Undead.