Nine children's ride to an elementary school was interrupted Tuesday morning when their school bus veered off the road and crashed into a Montgomery County house.

None of the children was injured in the crash, which occurred at 7:45 a.m. in a Blue Bell neighborhood, police said. The driver, who police also said was uninjured, was taken to Abington Memorial Hospital for observation.

One resident was inside when the school bus drove into the large white Colonial house, police said. He was on the second floor and was not hurt when the bus traveled across the front lawn and slammed into a front door and window of the home at Windermere and Knightsbridge Drives.

The crash left a large hole in the front of the house and damaged the second-story facade. The county's estimated market value of the house is about $700,000.

The students, who attend St. Helena School in Blue Bell, and the bus driver left the bus through the rear emergency door, police said.

A neighbor, Adam Glazer, told the Associated Press he saw the bus accelerating up the winding street and wondered if it would stop. He said the bus swerved and knocked over a street sign before crashing into the house. A student then opened an emergency exit door on the bus and led her classmates out the back.

"Kids were very calm, surprisingly calm. They were talking amongst themselves," Glazer said. "Nobody was hurt, and everybody got lucky today."

The school's principal, Sister Cathe Shoulberg, told 6ABC the 58-year-old driver evidently blacked out before the crash.

The Whitpain Township Police Traffic Division is investigating the crash.