This study investigated the effect of Classroom Management strategies on Physics students' academic performance in Akamkpa Local Government Area of Cross River State, Nigeria. The main objectives were to examine the impact of Classroom Management approaches, gender differences, and age groups on students' achievement in physics. The research employed a quasi-experimental design, with senior secondary school two (SS2) Physics students randomly assigned to experimental groups receiving authoritative or inclusive classroom management interventions, and a control group. Data were collected through Pre-tests, Post-tests, Classroom observations, and student survey over a four-week intervention period. The study sample consisted of 152 SS2 Physics students, and data analysis was conducted using analysis of covariance (ANCOVA).The findings revealed a significant positive effect of Classroom Management Strategies on student academic performance in Physics. Both the authoritative and inclusive approaches resulted in substantially higher average scores compared to the control group, with the inclusive style yielding the highest achievement. A large effect size indicated that Classroom Management Strategies explained a substantial portion of the variance in student performance. While gender alone did not have a significant main effect, there was a notable interaction between gender and Classroom Management Strategy. Male students performed better under authoritative management, while female students excelled in the control group. Interestingly, the inclusive strategy led to similarly high performance for both genders, suggesting its effectiveness in enhancing physics performance regardless of student gender. The study also found significant main effects for both Classroom Management Strategies and age groups on student academic performance in Physics. However, the absence of a significant interaction effect indicated that the impact of classroom management strategies on academic performance was consistent across different age groups. These findings underscore the importance of implementing comprehensive classroom management strategies and considering students' age when developing instructional approaches to optimize learning outcomes in physics education.