The practice-based research focus of this dissertation was the under preparedness of Liberian secondary school students for the newly introduced school leavers' external examinations and tertiary education. The problem addressed by this qualitative exploratory case study was that the successive decimation of the Liberian educational system resulted in insufficiently trained and inadequately supported teachers, even in Monrovia. The purpose of the study was to examine the perceptions of the principals and teachers about teaching as they considered the performance of West African Senior Secondary Certificate Examination (WASSCE) exam candidates at a Liberian senior high school. The conceptual framework was based on the work of four educational researchers--James Stigler, James Hiebert, John Hattie, and Carol Dweck--who focused on the individual teacher's responses in the classroom rather than on enhancing teacher qualifications or changing curricula. Three principals and 10 teachers were interviewed mainly on site at the high school. The Braun and Clark method of reflexive thematic analysis was applied with manually coded data. Themes indicated that stakeholders lack key information about exam requirements and student performance which influences their expectations, teachers whose students were the most successful demonstrated strategic planning in their responses, and only some teachers viewed peer collaboration as a source of support. A recommendation for practice is to increase teachers' information about the exams and opportunities to collaborate so that they can plan classroom activity effectively. A couple of recommendations for future research are an exploratory case study on the perceptions of students and parents about the WASSCE performance and an action research study on supporting teachers with their thinking in the classroom through providing WASSCE mark schemes and examiners' reports. [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.]