This study was conducted purposely to assess the degree of school effectiveness among public secondary schools of Zamfara State, Nigeria. In order to achieve this fundamental objective, one research question was formulated. A descriptive survey research design was adopted in the study. Population of the study comprised the entire 2361 classroom teachers deployed in the 158 public secondary schools of Zamfara State-Nigeria. From the population of the study, a sample size of 266 teachers was extracted using a â€˜Multistage Random Sampling Techniqueâ€™. A semi-structured questionnaire developed by Lezzote and Snyder (2011) on a five Likert type scale instrument with 21 items was employed as an instrument for data collection. The instrument composite reliability was computed using Cronbachâ€™s alpha method and obtained the value of .949. All data covered in the study were collected through a field survey approach. Analytically, the current study discovered that, the degree of school effectiveness was at a high extent with mean score (M=3.68, SD=0.15). Based on this finding, the paper recommends that, stakeholders in educational sector comprising governmentâ€™s ministries, departments and agencies, policy-makers, secondary schoolsâ€™ principals, instructional teachers as well as the learners and their parents/guardians should reciprocally work together in the process of appropriate perpetration and advancement of effective school system and its practices.