The models of teaching are systematic tools that allow teachers to vary their classroom pedagogical practices to meet the needs of all learners in their classroom. This study was designed to determine key factors that influence teachers' decisions when determining a model of teaching for classroom instruction and to identify how teacher training on the models of teaching in a pre-service or in-service program affect teachers' fidelity to these pedagogical practices. In this mixed method study, participants responded to both survey and interview questions to determine their understanding and usage of the models of teaching. Results indicated that teachers trained in the models of teaching in a pre-service program were more likely to use the models correctly in classroom instruction. Additionally the findings suggested that teachers identified similar factors that influenced their selection of pedagogical practices for classroom instruction regardless of the time period in which they were trained in the models of teaching. The interview results found that teachers indicated student ability level, allotment of time for lesson, lesson objectives, academic content standards, and the group of students being taught as the factors that greatest influenced their decision when selecting a model of teaching for classroom instruction. A foundation in the models of teaching as a use for pedagogical practice ensures a teacher will be more likely to use the varied frameworks for classroom instruction (Eggen & Kauchak, 2006: Hess, 2003; Miller, 2008). [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]