This study aims at providing a detailed analysis of the impact of poverty on the academic performance of students in public day secondary schools in Thika sub-county, Kiambu County, Kenya, with a focus on Kamenu Secondary School. The study used a qualitative phenomenological method to gain an understanding of the complex dynamics of poverty and academic achievement among students in the school setting. The findings of the study were supported by the qualitative data on the educational resources and students' characteristics, socio-economic statuses, and poverty levels of their households. The results of the hypothesis testing showed that health and nutrition, educational resources, socioeconomic status, and health and nutritional status play a crucial role in determining the performance of the students in their academic work. This study, therefore, supports our understanding of how poverty affects the academic work of students enrolled in a public day school in the Kamenus Secondary School, Thika Sub-County, Kenya.