The aim of this study was to assess the role of heads of schools in ensuring effective leadership in public secondary schools in Geita Town Council. The study was guided by three specific objectives which are to determine leadership styles used by heads of schools in ensuring effective leadership, to determine how the implementation of supervision activities is done by the heads of schools in ensuring effective leadership and to explore the challenges facing heads of schools in the supervision of activities towards ensuring effective leadership. The study employed mixed research approach with a convergent parallel design. Quantitative data were collected using questionnaires while interview was used to collect qualitative data. The study used a sample size of 132 respondents comprising of 1 DEO, 3 WEO, 6 Heads of schools, and 122 Teachers. The quantitative data were descriptively analysed by using Statistical Package for Social Science (SPSS) Version 20 while thematic analysis was employed in analysing qualitative data. The study established that heads of schools played their roles in ensuring effective leadership through implementing effectively the supervision activities in the schools. The study findings further revealed that the District Education Officer and Ward Education Officers contributed significantly in implementing supervisory activities for good outcomes in their schools. The study revealed that there were multiple challenges which faced school leadership and the challenges hindered heads of schools in implementing supervision activities. The study recommends that the government should fund education as well as strive to allocate adequate funds to the education sector for the purpose of improving school infrastructure and equipment.