The study investigated interest levels and differences in mathematics among O-level students in Wakiso District. Since interest is a psychological state, people can be unaware of it, making it simple for educators to presume that it is or is not present. In the current study, mathematics interest levels among Senior Three pupils in the Wakiso district were evaluated, and narratives from the students and teachers revealed the causes of the low interest. Three hundred and thirty-two students were used for the quantitative data; six students from each school took part in focus group discussions, and one O-level mathematics teacher from each school took part as key informants for the qualitative data. Quantitative results revealed that; students had high interest in mathematics (84%), had more situational (M = 37.00, SD = 8.10) than individual interest (M = 30.67, SD = 5.82). There were significant gender differences in overall interest Males (M = 73.61, SD = 13.22) than females (M = 69.93, SD = 13.60) individual interest Males (M = 31.32, SD = 5.76) than females (M = 30.03, SD = 5.83), and situational interest males (M = 38.19, SD = 7.81) than females (M = 35.83, SD = 8.21), p < .05. in mathematics, but not in other demographics. Qualitative findings, however, revealed low interest in mathematics, pointing out various reasons for their low interest (mathematics being tough, complex, boring, full of calculations, unrelated to ral life, intended for the intelligent, previous poor performance). According to the study's findings, the challenge of low interest should not be left to students only, but all stakeholders in education should take part in developing and maintaining students' interest in mathematics. There are still gender differences in mathematics interests, which impacts females' interest in the subject