This paper deals with the study of consistencies of performance in mathematics of 21 randomly selected schools in Nalbari District of Assam. Ideally the performance in mathematics should be improved consistently. The mathematics performances measured by the class average scores of three tests viz. Class VIII Annual Examination, Class IX Annual Examination and Mathematical Ability Test (MAT) conducted in Class X were used to investigate the consistency of performances of all the 21 schools. For examining the consistency it was assumed that each individual learner was subjected to identical treatments in the three consecutive years. Consistencies of current Class X students of each school were evaluated through a standard procedure. Overall, only 28.28% learners are showing consistent improvement in mathematics performance. On the other hand, performance of 18.03% learners is deteriorating. Remaining (more than half) population of learners indicated complete lack of consistency. Later key results were analyzed using the educational environment factors. Consistencies n performances cannot be fully explained by the managerial conditions of the schools. In spite of better managerial inputs, only 18.75% learners of an urban located government school are showing consistent improvement in mathematics. Similarly, in spite of better educational environment, about 90% of the learners of one urban located private school could not show consistent improvement in mathematics.
