This paper examines the level of corruption in educational system focusing on the private secondary schools in Nigeria. The paper argues that corruption is a general disease within the private school proprietors, policymakers, examination councils, teachers, supervisors and invigilators, and above all, leads to the abuse of teaching as a profession like other professional bodies in Nigeria. In all human societies, particularly the modern ones, education therefore remains one of the most powerful instruments for both the development of man and transformation of the human society. However, the efficacy and efficiency of education as an instrument of transformation depends entirely on how all the stakeholders, students as individual’s, parents, teachers, proprietors of private schools, policymakers, examination council, ministry of education and the government manage, execute and implement policy on education meant for the upliftment of educational sector. In this study, the factors, types, costs, causes of corruption and challenges facing private secondary schools were examined. Solutions and strategies to tackle the challenges were also examined.