CALGARY - The day before a Calgary school bus smashed into a parked gravel truck, killing a young girl, another driver was so concerned by how badly it was being driven he considered calling 911.

Pierre Lamarche told a fatality inquiry Tuesday that he spotted the small orange bus speeding and veering wildly the afternoon of Oct. 17, 2007.

Lamarche, himself a bus driver, considered the driving so "erratic, unprofessional and dangerous" that he manoeuvred his own vehicle closer so he could take down the driver's information and make sure no children were riding inside.

"Had there been some kids on the bus I would have called 911, that's how I felt about it," he testified at a fatality inquiry Tuesday.

Lamarche called the school named on the side of the bus and left a detailed message about the driver, checking back the next morning to see whether it had been picked up.

On that morning he heard on the radio there had been a bus crash in the city. It wasn't until later that day, when he flicked on the news and saw the mangled wreckage at the side of the road, that he realized it was the same bus he had reported a day earlier.

Kathlynn Occena, 9, died in the crash after the bus scraped along the side a gravel truck parked in the emergency lane of a busy Calgary highway, shearing off the entire right side, before hitting a light post.

Driver Louise Rogers pleaded guilty to careless driving and was fined $2,300. The inquest, which can't lay blame, was called to look at ways similar accidents can be prevented in the future.

A teenage boy who was sitting directly behind Kathlynn described a routine trip most of the way to school before the collision.

Coleton Patton, now 16, said Rogers had to wait several minutes for the Kathlynn and her sister to board, and then drove aggressively and more quickly to make up for time lost.

He was passing a handheld video game back and forth with a friend as the bus merged onto the highway.

He remembers it climbing a hill. Then, nothing until minutes later.

"There was a firefighter holding my neck so I wouldn't move," Patton said calmly, testifying by video link from Kelowna, B.C.

Witnesses to the crash testified hearing children screaming as bystanders tried to help them off the bus before emergency crews arrived.

"Children crying and chaos and people helping get these children out of the bus," said Judy Ferber, recalling outside court what she saw when she arrived.

Ferber was so shaken by the experience she now takes a different route to work every morning.

"It was horrible. It was horrible," she said quietly. "Today when I see school buses or I see a vehicle parked on the side of the street, it makes me nervous and I try to move over."

Patton said he recalled Rogers fighting with someone on her cellphone while waiting for Kathlynn and her sister. Rogers would use the phone about twice a day, often while driving, he said.

Another student, Loueye Haymour, recalled seeing Rogers put wires to her ears after leaving his house, although he couldn't tell whether the headphones were attached to a music player or cellphone. He said she was driving quickly and "she was maybe not paying attention to the road."

Several witnesses testified about the conditions that morning. One said the parked gravel truck had its hazard lights flashing at least one point in the morning. Another said she saw the bus slowly drifting towards the emergency lane as it approached the truck.

Children were quickly whisked off to hospital as emergency workers arrived on scene.

Lamarche said he isn't sure what would have happened if his complaint had gotten to supervisors more quickly the day before the crash, but he still feels very strongly about making the call.

"In this case, knowing what the cargo is - kids - it felt it was my duty to at least inform the school."