This study focused on determining the effect of the use of Gen-Math Machines which are manipulatives or teaching tools in one of the core subjects of Senior High School, General Mathematics. The teacher-researcher asked the learners to develop Gen-Math Machines that would elicit the things that they are learning in General Mathematics, and those machines were used in enhancing skills of learners in General Mathematics. One hundred forty-four became the respondents for this study, and they were the grade 11 learners of Talangan Integrated National High School, school year 2017-2018. Data came from the result of a 20-item quiz given after teaching sessions on the topic Exponential and Logarithmic Function ? one set of data using teaching process without the aid of Gen-Math Machines while the other set of data came from teaching process with the aid of Gen-Math Machines. For teaching process without the aid of Gen-Math Machine, the learners got a mean of 9.94 and an SD of 4.38 from a 20-item short response quiz. On the other hand, learners got a mean of 14.65 and an SD of 8.87. Learner to a higher mean when manipulatives are used during the teaching-learning process. Using t-test for independent samples, it was found out that teaching process has significant effect to the Mathematical performance of learners. The Gen-Math improved learners? concept and skill in mathematics. Recommendations to mathematics teachers, department head, school heads, family, community and future researchers were left at the end of the study.