The crash happened just before 2 p.m. at Grandview House Preschool in the 1200 block of North Pacific Avenue, next to Temple Sinai of Glendale.
A preliminary investigation found that a female driver was attempting to make a U-turn in the parking lot when she accelerated and struck a parked vehicle, Glendale police Sgt. Gaik Pobokhian said. The driver's black Infiniti tore through a gate and crashed into the room.
Children part of a summer camp were inside the classroom at the time of the crash.
Eight children suffered minor injuries and were taken to local hospitals. They were later released to their families.
Mahmoud Hajazi said he quickly rushed through the crumbling walls of the building to save the children inside.
"The teacher was screaming and yelling, and the kids (were) on the ground," he said.
Another witness described a chaotic scene following the collision.
"The whole gate was on top of the kids... It was like in a horror movie. I was shocked," said Vigen Hovsepyan, who helped rescue the kids.
Pobokhian said the crash appears to have been an accident and that the driver is cooperating with the investigation. He added that police found no signs of impairment during a DUI investigation.
The driver was not injured.
In the aftermath of the crash, damage to the classroom was visible, with the wall destroyed and debris scattered throughout the area.
Police said the driver has no affiliation with the school.
It remains unclear how many children were inside the classroom when the crash occurred.
Fire department crews were assessing the structural integrity of the building as the investigation continued.
It's unclear when the school will reopen.