Research in teaching and learning in higher education in the last fifteen years addresses the importance of integrating disciplinary ways of thinking -- i.e. an understanding of the ways that questions are asked and investigated within disciplines -- in undergraduate courses. However, the application of this emergent research varies in history departments and in large lecture survey courses. This study addresses the gap in research about effective modes for introducing disciplinary thinking in a large lecture history course through the means of the threshold concepts framework. This dissertation contributes to three areas of research in higher education: application of threshold concepts at the course level; what this application looks like in terms of practices at the discussion section level; and the role of the teaching assistant in his or her own development in teaching history and within the discipline.

This study looked at how threshold concepts were introduced in a large lecture history course. The analytical framework for viewing the results provided a lens to look at how the concepts were introduced and carried throughout the course. This framework, shaped by the situated learning and threshold concepts literature, looked at the "careers" of the concepts and how they were woven through a large learning system from professor to TAs to students.

In order for the careers of the concepts to carry through the course, certain teaching capabilities need to be in place to ensure the concepts reach students. The methods used to determine the uptake of concepts in the TA discussion sections were classroom observations, online surveys and interviews. Results show that teaching assistants are a crucial link for the careers of the concepts within a large lecture course. Moreover, teaching assistants' orientation to threshold concepts contribute to an explicit emphasis on the disciplinary concepts within their own work as disciplinarians and researchers. Tracing the careers of these concepts yielded more information about what is needed within the large course system in terms of the types of processes that need to be in place to support the inclusion of the concepts in the course. Threshold concepts afford faculty an opportunity to rethink the goals and principles that drive their course. Translation and framing of these concepts represented the threshold capabilities needed on the part of the teachers (both the professor and TAs) to support the movement of concepts from professor to students. The historical thinking strategies, such as analyzing primary sources, represented the particular threshold actions needed to support students in moving through thresholds to the discipline. While this is a baseline qualitative study of one large lecture course at UCSB, implications of this work contribute to graduate student teaching development and threshold concept course design.