Online gaming has the potential and may be utilized effectively to enhance teaching and learning, engage students, encourage, and reinforce their learning, have an impact on students academic achievement, and support proficiency learning. This study used the quasi-experimental two-group pretest-posttest design to determine the effects of online games on the academic performance of the students. This research summarized the results from the experiment done to determine how online games affect students academic performance in Science 9.T-test results revealed a significant difference between the experimental group, which received instruction through online games and obtained a mean score of 23, and the control group, which received a mean score of 13. The control group, which received the same Science 9 lessons but was spared the use of online games, scored poorly. The researcher proposed to the government to fund educational online games for secondary schools and encourage science teachers to change the talk-and-chalk teaching style in favor of using more advance tools and experimenting with new methods of science learning.