The student was walking home from Central Middle School on Arroyo Avenue near Cedar Street at about 3:28 p.m. when a dark colored four-door sedan slowed down in the roadway near to her, according to the San Mateo County Sheriff's Office.
The driver proceeded to expose himself to the young girl, sheriff's deputies said.
The student immediately turned around and walked the opposite direction, returning to her school, where she reported the incident to school officials.
The student said the vehicle had a young child, approximately 6 years of age, sitting in a car seat in the right rear seat of the vehicle. She said the vehicle drove westbound on Arroyo Avenue toward Cordilleras Avenue.
School officials immediately notified the San Mateo County Sheriff's Office, sheriff's deputies said.
Patrol units from both the San Mateo County Sheriff's San Carlos Bureau and from the South County responded.
A San Mateo County alert went out to San Carlos residents and a radio broadcast was transmitted to San Mateo County police agencies.
The driver was described as a Hispanic male between the ages of 20 and 30 years of age. The victim described the man as chubby. The suspect was wearing a black short-sleeved shirt, blue jeans and had a buzz-cut hairstyle, according to the San Mateo County Sheriff's Office.
Anyone with information regarding this incident is asked to cal the San Msteo County Sheriff's Office at (650) 802-4277.