Steve Levitt is hot on the trail of another scoop:
Along with Brian Jacob, I have written two papers that explore a very different concern regarding high-stakes testing — cheating on the part of teachers and administrators. As incentives for high test scores increase, unscrupulous teachers may be more likely to engage in a range of illicit activities, such as changing student responses on answer sheets, or filling in the blanks when a student fails to complete a section. Our work in this area represents the first systematic attempt to identify empirically the overall prevalence of teacher cheating and to analyze the factors that predict cheating.
…Empirically, we find evidence of cheating in approximately 4 to 5 percent of the classes in our sample…this estimate is likely to be a lower bound on the true incidence of cheating.