Families of the four Lee High School students who died in the 2006 school bus crash in Huntsville expected revelations in last week's National Transportation Safety Board report. They didn't get them.

Instead, those families and state education officials heard much of what already was known: The crash probably occurred when a car driven by another Lee student collided with the bus while traveling on Interstate 565. No hidden cause was uncovered. The basic facts of the tragedy remain the same.

But don't believe the NTSB report was a wasted effort.

If anything, the government investigation proved that oversight of school bus operations must be stringent and airtight. Nothing else is acceptable. Any lapse in supervision of those who drive school buses, manage bus plans or coordinate bus repairs is a danger to the safety — and the lives — of children.

In its report, the NTSB said the bus' driver, Anthony Scott, was not wearing his seat belt. The crash ejected Scott from the bus — meaning no one was at the controls to attempt to stop the bus after it impacted a retaining wall on the interstate.

The NTSB report also said Scott had used marijuana within a week of the accident, but that he wasn't impaired by the illegal drug on the day of the crash.

No criminal charges were filed against Scott. Given the report's findings, that seems the appropriate decision. Positively, the crash has already led to several changes in national regulations for lap-and-shoulder belts and higher seat backs for certain buses.

However, the report does underscore the need for school officials to assess all aspects of bus operations. Scott wasn't wearing his seat belt — which didn't cause the crash, but certainly played a factor in his inability to control the bus after it hit the wall.

Additionally, the report's inclusion of marijuana use was troubling. Scott may not have been under the influence on the day of the Huntsville crash, but it is not a comforting sign for parents when they hear that an Alabama school-bus driver was linked to illegal drug use.

The actions of one person do not tarnish the collective reputation of the state's school bus drivers. Their dedication to the safety of the children they transport should not be questioned.

But parts of the NTSB report on the Huntsville crash give us pause. Checking the state's school bus operations seems a wise choice. We can never be too careful in protecting children's safety.