This paper discusses three schools that have started a program designed to include at-risk students in gifted and talented programming by promoting systemic changes in student identification for gifted and talented classes and differentiated instruction in the regular classroom setting. The study conducted teaching observations and analyzed surveys of students, parents, and 21 teachers in three middle schools in three Kentucky school districts to determine whether a combination of sustained school-wide professional development and in-depth training of a smaller cadre of teachers is an effective model for effecting changes in teacher behavior. The school-wide professional development program was found to be effective in providing "awareness" level instruction to teachers and sensitizing them to the needs of disadvantaged gifted students. However, the on-going training provided to a cadre of teachers seeking gifted education teaching certification was found to be key to systemic change at each of the three schools. Teachers in the buildings turned to the cadre of teachers to help them implement the practices they had learned in the professional development and to help them problem-solve when the practices did not work smoothly. (Contains 44 references.) (Author/CR)