....utter bunk.
Writer acts like an apologist for the school systems, who cannot afford to put seat belts in their buses and hope not to face the liabilities of injury by such excuses. This as usual is money not science nor true care, as characterizes America.
Galileo's laws of motion ensure that a moving body will tend to stay in its current motion unless acted upon by an opposing force. thus, when the bus collides with anything powerful enough to suddenly stop it, the other contained objects [the kids] will continue to go forward until they are opposed by a force which brings their momentum to a sudden stop.
Bus passengers survive this seatbelt-less situation by the fact that the drivers are usually safer than average, and the bus is rarely going very fast, and it is so heavy that it smashes the smaller cars thus coming to a less violent stop. A smash-up with a heavy object like a bus with a more fragile object like a car is a type of "inelastic collision" wherein the crunching up of the car gradually dissipates the momentum of the bus to allow interior objects a less sudden termination of velocity.
That happy set of circumstances however does not cover all situations, and since we're dealing with kids here, the risk-taking economically-forced status of the school bus system remains.
This guy is so immature that he probably thinks he's writing about something funny.