Early Years Education (EYE) is the crucial stage in the child’s physical, social, emotional, and intellectual development. This study, therefore, sought to evaluate the effectiveness of teacher supervision practices in the implementation of the EYE program in the Khwisero Sub-county. The study which targeted key education stakeholders in EYE adopted a cross-sectional survey research design. Stratified random sampling and purposive sampling were used to select 10 schools, 10 head teachers, 10 teachers in charge, 1 program officer, 4 ward representatives and 50 assistant teachers. The questionnaire, interview guide and document analysis guide were used for data collection. Frequency of supervision is key to the effectiveness of teacher supervision practices because it affects the adequacy of teaching resources, the development of necessary learning skills, and effective time management. From the findings, it was noted that there are various areas of teacher supervision, which are not adequately addressed as indicated by some respondents, including teaching and learning resources, time management and teacher professional records. By implementing effective supervisory practices, schools can create an environment that supports high-quality education and fosters continuous improvement in learning outcomes. Preparedness ensures that teachers have the necessary skills, resources, and time management capabilities, hence directly influencing the adequacy of teaching resources, learning skills, and time management. Generally, respondents thought that supervisory practices in place were effective, though the degree or intensity of effectiveness varied. Therefore, the study recommended that Early Childhood Development and Education (ECDE) stakeholders support the supervision initiatives in place for effective curriculum implementation of the EYE program.