Oklahoma’s schools superintendent said Thursday that her chief of staff calling school administrators “dirtbags” in a personal Twitter post was a “poor choice of words”—but called a lawsuit targeting parents of special-needs children that prompted the comment vindictive and “groundless,” the Associated Press reports. In her Sept. 7 posting, which was first reported by the Tulsa World, Jennifer Carter referred to a lawsuit the Jenks and Union school districts brought against the parents of special-needs students who had sued the districts…