The Talent Development Middle School model was created to make a difference in struggling urban middle schools. The model is part of a trend in school improvement strategies whereby whole-school reform projects aim to improve performance and attendance outcomes for students through the use of major changes in both the organizational structure and the educational processes of middle schools. The models that function in this way--broadly referred to as "comprehensive school reform (CSR) models"--have been developed both nationally and locally, and they receive support from a combination of federal, state, and local funding as well as from private foundations. Talent Development has been a key target of federal resources earmarked for expanding the use of CSR initiatives in middle schools. The model reflects many of the core principles embedded in the CSR movement. School-level structural changes, for example, create more personalized learning environments for students and teachers; curricular changes improve the rigor of coursework and raise teachers' and students' expectations; and professional development for teachers fills gaps in both content knowledge and pedagogy. The findings in this report--which offers an initial assessment of the first and most intensive effort at scaling up the use of the Talent Development Middle School model--indicate that Talent Development had a positive impact on eighth-grade math achievement and exhibited modest impacts on attendance rates. At the same time, the model produced an inconsistent pattern of impacts on eighth-grade reading and had few significant impacts on outcomes for seventh-grade students. This assessment is based on an innovative analytic methodology that relies on a combination of before-and-after and comparison-schools methods. Although the findings offer hope that the Talent Development model can improve academic outcomes, at least in math, for middle school students, more data collection and analysis are needed before definite conclusions can be drawn. A subsequent report will track outcomes for two additional years of implementation and will provide a clearer picture of the potential for improvements in middle school achievement to lead to greater persistence in high school and, eventually, to graduation. Appended are: (1) Tables for Eighth-Grade Students in Early-Implementing Schools; and (2) Tables for Seventh-Grade Students in Early-Implementing Schools. (Contains 4 boxes, 11 figures, and 13 tables.) [Dissemination of MDRC publications is also supported by Starr Foundation.]