The Office of Shared Accountability conducted an evaluation of the implementation of the third and final year (2012-2013) of the "Science, Technology, and Engineering Leadership Program" (STELP) in Montgomery County (Maryland) Public Schools (MCPS). Funding for STELP, including the evaluation study, is provided by a grant from the Howard Hughes Medical Institute (HHMI) to MCPS. This evaluation report addresses the third year of STELP with a total of 35 school-based staff members participating during year three. The focus of this evaluation was on implementation of the program in terms of continued training of a group of teacher leaders to further develop and refine online professional development products for other MCPS science, technology, and engineering (STE) educators to view. This study used a nonexperimental design utilizing a variety of data collection methods that included: review of program documents and training records, surveys, and review of the online product training plans created by teacher leaders. Findings are organized by evaluation questions and recommendations are provided. The following are appended: (1) Training Sessions' Feedback Surveys; (2) Example of Online Module Survey Questions; (3) Secondary Science Resource Teacher Survey; (4) Module Training Plan Template; and (5) Summary of Content of STELP Online Professional Development Training Plans.