The study focused on the development and validation of reading intervention materials (RIM) in selected topics in El Filibusterismo. The study aimed to find answers to the following: a) to know the least mastered skills in learning El Filibusterismo that can be subject of development of Reading Intervention Material, b) To know the level of performance of the learners before and after using the RIM based on their pretest and posttest mean scores, c)To identify the significant difference between the pretest and posttest mean scores of the learner-respondents and d) To evaluate the developed RIM by the teacher-respondents in terms of the following criteria using the LRMDS tool: a) Content, b) Format, c) Presentation and Organization, and d) Accuracy and Up- to-Datedness of Information. The hypothesis of this study claimed that there is asignificant difference in the level of performance of Grade 10 learners in their pretest and posttest scores. The study was limited to Grade 10 Filipino subject teachers and leamers at Tala High School in North Caloocan City during the SY 2018-2019 The research design and methodology of this study included the use of pretest and posttest for the 50 Grade 10 leamer-respondents from Tala High School in North Caloocan City. Likewise, eight teacher respondents, including the school head, participated in the LRMDS evaluation test. Thus, the researcher presented a survey questionnaire to the teachers based on the criteria given by the LRMDS. For development, the pretest, posttest and (RIM) were applied and validated. This study used the following statistical tools: a) weighted mean and b) t-test for correlated sample. The following findings were obtained: First, the topics selected for development of Reading Intervention Materials (RIM) were: Sa Ibabaw ng Kubyerta and Sa Ilalim ng Kubyerta. Second, the least mastered topics that became subject for the development of the researcher's material were: Nakikilala ang mga tauhang inilalarawan sa bawat bilang, Nabibigyang- kahulugan ang matatalinghagang pahayag o kasalungat na ginamit sa pangungusap, Napipili ang angkop na detalye para sa mga sitwasyon na mula sa akda, Naipahahayag ang sariling paniniwala at pagpapahalaga kaugnay ng mga kaisipang namayani sa kabanata at Natutukoy ang kahulugan ng mga salitang ginamit sa pangungusap. Third, based on the learners' pretest and posttest mean scores, there was a significant difference before and after using the RIM in selected topics in El Filibusterismo. Fourth, the developed RIM was validated based on the criteria of LRMDS for New Print Materials In view of the foregoing findings, the researcher arrived at the following conclusions: First, the least mastered skills and topics could be the bases for developing RIM. Second, the posttest mean scores were higher than the pretest mean scores indicating that there was a significant difference between the two. It implies that the learners performed well after using the RIM. Third, this study shows that RIM was highly effective in terms of the ways leamers learn. Fourth, the developed RIM of the researcher was acceptable and applicable to the teachers in helping learners to learn the skills and enhance performance. The foregoing salient findings of this investigation, it hereto recommends that a parallel study be pursued so as to validate the claim in this investigation. Likewise, it was recommended that this study be made the basis in proposing RIM which could be included in the design of a school's learning action cell activity.