Leading a whole-class discussion is a complex and critical skill, and pivotal to learning and achievement. Classroom teachers have been challenged to engage students in meaningful dialogue, and successfully meet educational standards and requirements. Teacher education programs are responsible for preparing future candidates--preservice teachers--to be competent and knowledgeable in their ability to communicate effectively with students. Secondary-level preservice teachers often have inadequate skills, experience, and confidence in leading whole-class discussions. The problem that was examined was why secondary-level preservice teachers struggled using thought-provoking questions and dialogic tools that prevented them from leading stimulating, whole-class discussions. The purpose of this qualitative embedded, single-case study was to gain a deeper understanding of classroom discussion by addressing the research questions of how secondary-level preservice teachers used specific questions, and by examining preservice teachers' perceptions regarding the use of dialogic tools in leading whole-class discussion. The purposeful sampling included four secondary-level preservice teachers enrolled in a methods class in a teaching program in a small, mid-western college. Constant comparison analysis and triangulation of multiple data resulted in seven themes derived from the subunits of analysis associated with the theories of Bloom (1956) and Vygotsky (1978). The study's findings contributed to the literature on discussion practices at the secondary-level, with recommendations for teacher education programs and educators. Bloom's levels were essential in developing questions to foster discussion, and practice-based teaching methods strengthened preservice teachers' skills in leading classroom discussions. More research is needed regarding the implementation of dialogic tools that promote whole-class discussion at the secondary level. [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.]