The entire "school bus" story is a piece of right wing bullshitt based on someone from the right wing rag Front Page seeing a flood picture of school buses on the Associated Press page and automatically reaching the unsupported conclusion that school buses sat in the time of need jumping to the irrational conclusion that it was Mayor Nagin fault for not deploying the buses. Since Mayor Nagin has been working his butt of around the clock, he hasn't had time to respond to the ludicrous complaints of the armchair rescue specialists in the GOP.
The New York Times got to the truth of the matter, in their lead story this morning. The school buses had no drivers! The drivers (which are mostly women) that could reached prior to the storm were afraid to drive and refused to go to work when a monster hurricane was approaching New Orleans.
It was at that point Governer Blanco and Mayor Nagin began to work to get Greyhound buses deployed. Mayor Nagin never once made any comment, as the right wing press said he did about "Schools buses not being comfortable enough for evacuees and delaying the evacuation by insisting on a fleet of Greyhounds." That was just a right wing fantasy and a ludicrous story that began at NewsMax and in turn was covered by Front Page, but mainstream media simply refused to carry the story because it was a ludicrous story in the first place and had absolutely no sources for Nagin's comment.
End of story... End of right-wing bullshit.