This research presents results of a longitudinal study of a three-year in-service teacher professional development program that was focused on improving grades sixth through eighth students' science achievement, science literacy and increasing science interest in five urban middle schools. The key program elements included: (1) a summer teacher academy, (2) academic year use of lesson study, (3) instruction using integrated science, (4) science notebooks use, (5) instruction on science literacy and effective use of informational texts, and (6) inquiry-based instruction. The study was part of a larger research effort that investigated the effects of a comprehensive middle school science and mathematics teacher professional development intervention on students' science and math achievement. The purpose of the research for this particular work is to examine the impact of teacher professional development on teachers' science instructional performance and science teaching efficacy, and in turn, its impact on their students' science achievement as well as their literacy in and motivation for science. The research utilized a cross-school comparison methodological approach, which examined middle school students' achievement trajectories and employed a quasi-control condition in the program's first year of implementation, and in remaining years -- with multiple "doses" of an inservice teacher professional development intervention. Comparative and multi-level hierarchical linear modeling (HLM) was used for data analyses with multiple iterations of model fitting. Results of the research indicated that the professional development had multiple positive effects on the participating teachers and their students. School-wide teachers' science teaching efficacy increased for all participating teachers. The Academic Performance Indices (APIs) demonstrated growth for each of the five participating middle schools, and students' motivation for science and their science literacy had a positive effect on their science achievement. Furthermore, the participating students' achievement increased overall, with greater increases resulting from increased exposure to the teacher intervention (via proxy of the students' teachers). This teacher focused intervention is recommended for middle to large size middle schools and districts as it had moderate to highly positive effects on the teachers and students in the participating school district.