In December, after pushed by the Tampa Bay Times to examine complaints about some of its substitute teachers, the Hillsborough County School District started asking questions to the company that hires and supervises them, Kelly Services.What, district officials wanted to know, was the contractor's protocol for dealing with substitutes accused of wrongdoing in class? And what had become of dozens of subs who were the subject of complaints?Descriptions, contained in nearly 500 "Do Not Use" forms, included name-calling, bizarre behavior, hitting and slapping students, inappropriate speech and several teachers who slept through their shifts. For some of the substitutes, there were multiple complaints.The district gave Kelly – which is paid as much as $15 million a year – two weeks to respond. The letter implied that, absent a response, the district would reconsider the three-year-old relationship.It has been nearly four months and so far, no response.A second letter went out this week. "We must receive a satisfactory response immediately," attorney Jeff Gibson wrote.The Times placed a call to Kelly's media office and has not yet received a response. We will update this post when we do.