This study was aimed to find out from the teachers in Nigeria, their perception of the functionalism and their participation in the internal testing programme of secondary schools special reference to a state in southern Nigeria. A sample of 1,000 teachers was randomly stratified from the entire teachers' population of 6,000 in government-own secondary schools. The percentages and chi-square (x2) statistical tools were used. The three hypotheses of the study were accepted at an alpha level of 0.05. There was no statistically significant relationships found between the teachers' perception of the internal testing programme in their schools and their participation in the whole exercises viz: Their classroom instructional management functions; the guidance and counselling of their schools and the administration of their schools, respectively. The study recommends that the state start training and re-training programmes of the teachers in measurement and evaluation, principles practice methods and capabilities.