The study investigated the demographic variables as predictors of effective secondary school supervisory practices in the North-Central states of Nigeria. The purpose of the study was to determine the extent to which gender, experience, professional qualification and age can predict effective secondary school supervisory practices. The design of the study was correlational survey. Four research questions and four hypotheses guided this study. The target population consisted of 2,051 external supervisors from Ministries of Education, Teaching Service Boards, and Area Education Offices as well as internal Supervisors from Government Secondary Schools in the North-Central States of Nigeria. The sample of the study consisted of 528 respondents. Multi-stage sampling technique was used where random sampling technique was used to select three states out of the six states in the North-Central States of Nigeria while proportionate certified random sampling technique was used to select secondary schools in each of the sampled states. The instrument for data collection was researcher’s developed questionnaire titled Demographic Variables Supervisory Practices Questionnaire (DVSPQ). The instrument was face validated by two experts in educational administration and one in measurement and evaluation from Faculty of Education University of Nigeria, Nsukka. The overall reliability yielded 0.93 using Cronbach alpha coefficient Method. Data was analyzed using Pearson r and R2for answering research questions. The hypotheses were tested at 0.05 level of significance using linear regression analysis. The major findings of the study were that gender, experience, professional qualification and age to a little extent predict supervisors’ effective secondary school supervisory practices. The educational implications are that, the study has provided empirical evidence that gender is not a hindrance to supervisors’ effective secondary school supervisory practices; the finding of the study also shows that experience has little impact on supervisors’ effective performance among others. The following recommendations were made based on the findings, that the government can employ supervisors on equal basis not minding whether they are males or females; both experienced and inexperienced supervisors can be employed by the government since on-the-job experience is most important; the government can encourage supervisors to attain higher professional qualifications; both young and old supervisors can be employed and on-the-job training given to them during their service years.

School systems worldwide are faced with the challenge of how to improve teaching and learning outcomes which can be possible through effective supervision of schools. Supervision is the process of guiding, directing and helping the teachers in the improvement of the instructional process (Afianmagbon, 2004). Supervision is viewed as a process of directing, overseeing, guiding or making sure that expected standards are met (Igwe, 2001). Supervision can also be defined as that which helps to improve the teaching and learning processes in schools. It involves supervising teaching and classroom activities of the teachers (Igbo, 2003). Supervision can thus be regarded as an educational process that focuses on the improvement of teaching and learning processes in schools.