This study investigated, using pretest-posttest quasi-experimental research design, the effectiveness of guided multiple choice objective questions test on students' academic achievement in Senior School Mathematics, by school location, in Delta State Capital Territory, Nigeria. The sample comprised 640 Students from four coeducation secondary schools, randomly assigned to control and experimental groups. Four research questions and four null hypotheses guided this study. Three instruments, Mathematics Assessment Test (MAT) 1, 2 and 3 were used to collect data. Difference in Mean Academic Achievement was subjected to z-test statistic and was significant in favor of the experimental group. Implications and recommendations of the study were advanced.