This  study  investigated  the difference between mean academic achievement scores of male and female students taught upper basic education 3 mathematics using formative assessment practice in in Enugu East Local Government Area. One research question and one hypotheses guided the study. The researcher adopted the non-equivalent control group  quasi-experimental  design  using  a  sample  of  one  hundred  (100)  upper  basic  students selected from two thousand, seven hundred and thirty-one (2, 731) upper basic students in Enugu East Local Government Area of Enugu State. Multi-stage sampling procedure was used for the study. Related data for the study were collected using Mathematics Achievement Test (MAT)). A reliability coeficient of 0.98 was obtained for the instrument using the split-half method. One (1) mathematics  education  and  two   (2)  measurement  and  evaluation  specialists  validated  the instrument. Research  questions  were  answered using  mean  and standard deviation  (S),  while research hypothesis was tested using Analysis of Covariance (ANCOVA). The finding showed that that male and female students exposed to formative assessment practice in Upper Basic Education 3 Mathematics had almost equal achievement scores hence gender has no significant influence on the academic achievement of students in Upper Basic Education Mathematics (p < 0.467). Based on the findings, the researcher recommended that Curriculum designers should take into cognizance while designing tasks for learners, that learning in Mathematics is not solely a cognitive affair. Hence, Mathematics curriculum should be designed to include the use of methods/strategies and material/media which would make the learning of Mathematics very active, investigative and adventurous.