This explanatory mixed methods study explores rural Oklahoma STEM subjects and STEM elective teachers' professional experiences, including professional development and certification pathways. Participants completed the Teacher Beliefs and Attitudes Toward STEM Survey (T-STEM Survey, Friday Institute for Education Innovation, 2012) for teachers and a questionnaire with demographic and open-ended and selective response questions on student STEM opportunities and the benefits and barriers to teaching STEM integrated lessons in their districts. Data analyzed includes the Likert style T-STEM, questionnaire and five semi-structured interviews of rural STEM subject teachers; respondent data was sorted by district type (rural, non-rural; non-rural, rural by district size; NCES location code), a statistical analysis was conducted to examine differences between groups. The results are organized into two manuscripts, each answering a specific set of the overall research questions. Overall, the dissertation findings indicate no statistical differences between any groups when comparing data based on the teacher's district location and size. Differences were found when examining individual items such as specific instructional practices (working in small groups, using content-driven dialogue), teacher participation in professional development, and informal student opportunities related to STEM interests. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]