This action research study emerged in response to students' struggle to understand what critical thinking is and teachers' corresponding struggle to develop students' critical thinking skills. In my role as an instructional designer, I studied student and teacher reactions to interdisciplinary course design that used disciplinary inquiry, problem-posing, and concept-based online learning. The primarily qualitative study focused on students' reflections across five different social studies and English courses, along with interview data from their teachers and post-course survey data. Exploring how students experience instruction designed to develop their critical thinking skills and how instruction in critical thinking impacts students' critical consciousness, I found students can demonstrate substantial confidence in critical thinking and metacognition when instruction is explicit and strategic. Students were able to apply specific metacognitive strategies to their learning, and even when they struggled, they demonstrated astute awareness of their own thinking. Specific elements of critical consciousness evident in my data included students' seeing themselves, displaying empathy and criticality when instruction combined relevant concepts, showcasing disciplinary thinking skills, and responding to compelling content. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]