The idea of outfitting school buses with seat belts is not a new idea. Neither is the controversy over their need. Some Motor vehicle Safety experts disagree on how useful seat belts on buses actually are.
Bob Harmon, the state transportation coordinator for the Ohio Department of education told the Columbus Dispatch that seat belts on buses are not "absolute" despite a need to improve motor vehicle safety for children. And to be fair, the statistics agree. Nearly 75% of bus accident victims are in other vehicles. It's a simple matter of which vehicle has the force behind it to withstand accidents, and how much force that vehicle can withstand in the case of an accident.
Despite this, Ohio state legislatures still want to push forward with bus safety. Pushing the cost of already-expensive school buses up another $7000 apiece would be hard, especially given the 400 to 500 buses replaced each year.
Why doesn't the federal government require seat belts on buses? Because the data supporting their effectiveness is very inconclusive. In short, school buses are already really good at protecting passengers-seatbelts might not really do much more overall, and some experts think that the money could be better put toward researching more effective safety equipment.