Asian Journal of Education and Social Studies

Kenya introduced Competency-Based Education (CBE) to develop learners’ practical and 21st-century skills. However, implementing CBE in marginalized regions such as Wajir East Sub-County remains challenging due to limited resources, teacher shortages, and irregular learner attendance, making school leadership crucial in supporting effective learning outcomes. This study assessed the effectiveness of head teachers’ administrative strategies in achieving competency-based education (CBE) learning outcomes in public primary schools in Wajir East Sub-County, Kenya. This research was conducted on a positivist research paradigm. A case study design with a combination of quantitative and qualitative approaches was utilized. The study was anchored on instructional leadership theory. The population targeted were 279 teachers and 27 head teachers from all the 27 public primary schools in Wajir East Sub-County. Yamane's formula was utilized giving sample size of 173 respondents (158 teachers and 15 head teachers). Structured questionnaires were used to collect the data from teachers and interview guides with head teachers. The instrument reliability was confirmed by Cronbach's alpha at 0.837. An actual response rate of 95.4% was achieved. Descriptive statistics and Pearson correlation were used for analysis. The findings revealed a moderate overall effectiveness mean of 3.14 (SD = .78) and instructional supervision was the most effective (M = 3.22, SD = .81), while promotion of learner-centered teaching was the weakest dimension (M = 3.09, SD = .82). The effectiveness of head teachers' strategies was meaningfully correlated with CBE implementation outcomes (r = .687, p < .01) as a significant positive Pearson correlation was found. Qualitative findings from interviews revealed that while supervisory engagement produced observable improvements in lesson delivery, teachers frequently reverted to teacher-centered methods without sustained professional support and irregular learner attendance in nomadic communities undermined competency progression. The study concludes that strategy effectiveness is constrained by insufficient embedded professional development and structural contextual barriers unique to marginalized settings. It recommends establishment of school-based instructional committees, structured peer coaching frameworks, and context-sensitive formative assessment toolkits tailored to arid and semi-arid educational environments.