STEM educational reform encourages a transition from instructor-centered passive learning classrooms to student-centered, active learning environments. Instructors adopting these changes incorporate research-validated teaching practices that improve student learning. Professional development that trains faculty to implement instructional reforms plays a key role in supporting this transition. Effective professional development features authentic, rigorous experiences of sufficient duration. We investigated changes in the teaching beliefs of college faculty resulting from their participation in InTeGrate project that guided them in the development of reformed instructional materials for introductory college science courses. A convergent parallel mixed methods design was employed using the Teacher Belief Interview, the Beliefs About Reformed Science Teaching and Learning survey and participants' reflections on their experience to characterize pedagogical beliefs at different stages of their professional development. Qualitative and quantitative data show a congruent change toward reformed pedagogical beliefs for the majority of participants. The majority of participants' TBI scores improved toward more student-centered pedagogical beliefs. Instructors who began with the most traditional pedagogical beliefs showed the greatest gains. Interview data and participants' reflections aligned with the characteristics of effective professional development. Merged results suggest that the most significant changes occurred in areas strongly influenced by situational classroom factors. Introductory geoscience courses play a crucial role in recruiting new geoscience majors but we know relatively little about how students' attitudes and motivations are impacted by their experiences in geoscience classes. Students' attitudes toward science and its relevance are complex and are dependent upon the context in which they encounter science. Recent investigations into the attitudes of geoscience students have provided evidence to support this observation. We sought to expand this data set to provide a broader characterization of students' attitudes. We examined students' attitudes about the nature of science and its relevance before and after taking an introductory geology course. To characterize students' attitudes, we employed two quantitative instruments: the revised Scientific Attitude Inventory and the Changes in Attitudes about the Relevance of Science survey. Results show a negative trend in students' attitudes about the nature of science while their attitudes about the relevance of science were more variable. Our data support the findings of previous studies showing only minimal change in students' attitudes about the nature of science and its relevance after taking an introductory science course. The data also highlighted several misconceptions about the nature of science that could have implications toward future investigations of how geoscience courses impact student attitudes about science. There is consensus among industrialized nations that it is important for its citizens and leaders to be scientifically literate. Therefore, it is important for the educational system to provide students with pertinent scientific knowledge, an understanding of the scientific processes, and the ability to evaluate scientific claims. Students' attitudes toward science and its relevance are important aspects of science literacy. We sought to determine if the repeated and explicit exposure to socioscientific issues through the use of InTeGrate course materials would result in positive changes to students' attitudes about the nature and relevance of science. We collected data on student attitudes using the revised Scientific Attitude Inventory and the Changes in Attitude about the Relevance of Science survey in a quasi-experimental design over four semesters of an introductory physical geology course. Results show that the emphasis of socioscientific issues can influence both students' attitudes about the nature of science and their perceptions on the relevance of science. Changes were observed in data from both STEM and non-STEM majors. These findings have implications about how we select content for introductory science courses in general, and proves the utility of designing geoscience lessons based around socioscientific issues. [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.]