The "No Child Left Behind" legislation requires states to classify schools based on students meeting the state's academic standards. A combination of factors, including scores on state specific tests and nationally normed tests, can result in a school being awarded a low classification or a high classification. In the authors' state, schools in the low classification are labeled "underperforming," and schools that are persistently classified as underperforming can eventually be taken over by the state. Although "No Child Left Behind" was only recently passed, many states have been using both state-specific and nationally standardized tests for years. Teachers have been aware of their students' achievement levels based on those scores, but now that access to information is quick and public via the Internet and other media, that information is rapidly and widely disseminated. However, the implications of this public and open display of student achievement on teacher efficacy have not been investigated. The purpose of this study was to investigate the components of individual and collective efficacy within and between two groups of teachers attending a summer workshop who came from two different types of school districts. One group, which the authors call "low," came from a district where many of the schools had been labeled as underperforming and the other group, which they call "high," came from a district with few underperforming schools. The participants were 63 4th through 10th grade teachers who voluntarily participated in two-week, summer professional development workshops on mathematics problem solving. The workshops focused on helping teachers increase their own problem solving ability as well as improve their classroom problem-solving instruction. Findings indicate that these workshops increased the teachers' personal competence, presumably by increasing their knowledge of mathematics and mathematics instruction, but they did little to increase their perceptions that they could affect their students' achievement. (Contains 1 figure and 1 table.)