The current study employs a qualitative, exploratory case study method examining the classroom practices of three 5th grade science teachers from two intermediate campuses within a school district in the Southwest. The study explores opportunities and barriers to high level questioning by teachers leading to critical thinking. Qualitative data were collected through multiple sources of data collection including open-ended questionnaires, classroom observations, interviews, and a focus group. The data answer the following central question: What are teacher conceptions of critical thinking instructional practices delivered through high level questioning? Findings provide campus and district leaders, and teacher educators, information for developing teachers who ask higher level questions supporting critical thinking from the perspective of teachers themselves. [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.]