In learning and teaching process, learning gaps happen with the different intellectual abilities and attitude of students toward studies. The purpose of SIM is to motivate students, to learn and apply concepts and skills into real life situations. This study investigated the effectiveness on the performance level on parts and functions of plant and animal cells (Biology) using the Strategic Intervention Material (SIM). The teacher-made SIM focused on the least mastered skills. The researcher used descriptive and quasi-experimental research methods to determine the effectiveness of SIM. Respondents were given sets of SIM to be utilized and answered. A pretest-posttest design was used for comparison. The data collected were statistically treated through the mean, standard deviation, and T-test. Findings revealed that there was a significant increase in the performance level of the respondents after using SIM. This proved that the use of SIM significantly contributed to the mastery of the lesson presented. SIM should be adapted as an “aid” for instructional materials in teaching to facilitate learning and improve performance of students. SIM made by the researcher can be used by teachers to re-teach the concepts and skills. The implementation and development of SIM is highly recommended to elevate the quality of learning of students globally, not just in the Philippines.