Influence of Teacher Professional Development on Job Performance in Public Secondary Schools in Rongai Sub-County, Nakuru County, Kenya

AbstractThis study examined the influence of teacher professional development (TPD) on job performance in public secondary schools in Rongai Sub-County, Nakuru County, Kenya. Anchored in Knowles’ Adult Learning Theory, the study employed a convergent mixed-methods design, targeting 48 administrators, 285 teachers, 300 students, and one Sub-County Director of Education. Stratified, purposive, and systematic sampling were used to obtain 191 participants. Data collection involved questionnaires for teachers, administrators and students while interviews collected data from SubCounty Director of Education. Research tools were subjected through content and face validity through expert review. Quantitative Instrument reliability was ascertained with help of Cronbach’s Alpha which yielded a value of (α = .796). Reliability for qualitative data was ascertained in terms of their trustworthiness specifically for credibility and dependability. Quantitative data were analyzed using Statistical Package for Social Sciences version 25 to generate descriptive statistics that summarized data. The results were presented in frequency distribution tables. Pearson correlations was used to test the hypothesis. Qualitative data from interviews underwent thematic analysis and the results was presented in form of narratives and frequencies. Results revealed low teacher participation in TPD (28%) but significant positive relationships between TPD and performance indicators: lesson preparation (r = .45, p = .002), clarity of explanations (r = .50, p = .001), and motivation (r = .40, p = .005). Students reported notable gains in classroom engagement (81%), while 69% of teachers perceived limited benefits, citing weak leadership support (81%), funding constraints (72%), and content irrelevance (68%). The study concluded that contextually relevant, sustained, and mentorship-driven TPD enhances teacher effectiveness and recommends localized models emphasizing peer coaching, administrative support, and NGO partnerships.