This project entailed a three-year efficacy evaluation of the Computer and Team Assisted Mathematical Acceleration (CATAMA) Lab developed by the Center for Social Organization of Schools at Johns Hopkins University. The CATAMA Lab was proposed as an immediate and practical approach to addressing the different types of math deficits held by students at urban high-poverty schools. The Lab required only 1 teacher per school reducing staff and professional development requirements. It used multiple instructional techniques (including individualized computer instruction, direct instruction, pair and team learning, and individual instruction) to teach math concepts and skills. By taking the place of an elective it allowed students to continue with their on-grade math class. For a more detailed description of the Lab see Appendix 2. The original goal of the project was to establish the Lab at three urban schools serving high-poverty high-minority middle grade students (grades 5-8). Students underperforming in mathematics (as established by district standardized tests) were to take a trimester course of study in the Lab to increase their knowledge of math concepts and skills taught by a regular math teacher receiving extensive ongoing professional development. Students were to take the Lab as an elective course while continuing with their regular math class. From each school's pool of students eligible to participate, students were to be randomly assigned to take the Lab. An implementation analysis was to measure the teaching of the concepts and skills to be taught in the Lab. To evaluate the impact of the intervention, students' math achievement, as measured by standardized math tests, was to be compared to eligible students not assigned to the Lab. This report discusses the project in three sections: (1) A comparison of the actual project with the planned project; (2) The descriptive results from the project; (a) Description of the sample; (b) Description of implementation of the CATAMA Lab; and (3) The evaluative results from the project.