The authors sought evidence of the effectiveness of the TI-Navigator classroom networking system for the second year of a two-year research study of Texas Instruments classroom technology. This randomized control trial compared Algebra I and Geometry instruction using the TI-Navigator system, which includes the TI-84 Silver Edition graphing calculator, to instruction with graphing calculators alone. The technologies did not provide a separate math curriculum, but did not include curricular materials. The authors asked whether students in classrooms with access to the TI-Navigator system and training, achieve higher scores than students in classrooms receiving only graphing calculators and training, whether TI-Navigator has a differential impact for students with various incoming math achievement levels, and whether the impact depends on gender or English proficiency. For the most part, the experiment could not discern an impact as a result of providing the equipment and training for TI-Navigator. In Algebra, while they found no overall difference, there was some evidence of a small negative impact for students scoring "below basic" on the CST and, holding pretest score constant, for English proficient students. Overall, the authors found that the TI-Navigator affected the average number of minutes the technology was used. (Contains 16 figures, 60 tables, and 32 footnotes.)