The 12:50 p.m. incident occurred at the end of the lunch break toward the north end of the Elsie Allen campus in an area that houses Midrose, a small alternative school for students trying to make up academic credits. The suspect, whose name was not released because he is a juvenile, attends Midrose, which has about 70 students.
During the brief and bloody attack, another student tried to intervene and "pull the teacher and the other kid apart," Linscomb said.
That student wasn't hurt in the scuffle, and the teacher and the boy who attacked him both fled out of the classroom and into a courtyard. The teacher called 911. Students who witnessed the attack told police they saw the boy head north to a gate in the campus fence that led into the Bellevue Ranch neighborhood, Linscomb said.
Police found the teen about three blocks north of campus at a relative's home on Silver Spur Drive.
Officers found what appeared to be the boy's bloody clothes in the neighborhood along the youth's "escape route," Linscomb said. Late Wednesday, police had not yet found the pencil, he said.
A man who answered the door where the boy was taken into police custody said he was a relative and the boy lived elsewhere in Santa Rosa with his parents.
The man, who didn't want to be identified, said his family was struggling to understand what took place with the youth and that he was "sorry it had gotten to this point."
Police don't yet understand what might have motivated the attack, Linscomb said. The boy didn't have a known history of violence, he said.
The stabbing elicited a large-scale police response.
The entire 980-student campus was on lockdown. Students were quarantined in classrooms with the blinds drawn, lights off and doors locked. They were instructed to stay quiet.