MENINGKATKAN PEMAHAMAN REAKSI REDOKS MELALUI PROBLEM BASED LEARNING (PBL) DI KELAS XII MIA2 SMA NEGERI 9 KOTA KUPANG

Abstrak

Penelitian ini bertujuan untuk mengetahui peningkatan pemahaman konsep siswa pada materi reaksi redoks melalui penerapan model Problem Based Learning (PBL) di kelas XII MIA2 SMA Negeri 9 Kupang. Selain itu, penelitian ini juga menganalisis pengaruh PBL terhadap motivasi dan keterlibatan siswa dalam proses pembelajaran kimia. Latar belakang penelitian menunjukkan bahwa pemahaman konsep siswa masih rendah karena metode pembelajaran yang monoton dan kurang kontekstual, sehingga siswa kesulitan mengaitkan teori dengan kehidupan sehari-hari. Penelitian menggunakan metode eksperimen semu (quasi experiment) dengan desain pretest-posttest control group design⁴. Subjek penelitian adalah kelas XII MIA2 sebagai kelas eksperimen⁵. Data dikumpulkan melalui tes pemahaman konsep (pretest dan posttest), angket motivasi belajar menggunakan skala Likert, dan observasi keterlibatan siswa. Kriteria keberhasilan penelitian ditetapkan apabila minimal 85% siswa memperoleh nilai  ≥ 70 (KKM)⁷. Hasil penelitian menunjukkan bahwa penerapan PBL terbukti mampu meningkatkan pemahaman konsep siswa pada materi reaksi redoks. Nilai rata-rata pemahaman konsep meningkat secara signifikan dari 60 (pretest) menjadi 80 (posttest). Persentase ketuntasan belajar mencapai 88%, melampaui target keberhasilan penelitian. Selain itu, hasil angket motivasi menunjukkan peningkatan skor rata-rata dari kategori “cukup” menjadi “baik”, terutama pada indikator rasa ingin tahu dan partisipasi aktif. Observasi juga memperlihatkan peningkatan keterlibatan siswa, ditandai dengan keaktifan dalam diskusi, keberanian mengemukakan pendapat, dan kerja sama dalam kelompok.                                                                    

This study aims to determine the improvement in students' conceptual understanding of redox reactions through the application of the Problem-Based Learning (PBL) model in class XII MIA2 of SMA Negeri 9 Kupang. Furthermore, the study also analyzes the effect of PBL on students' motivation and engagement in the chemistry learning process. The research background indicates that students' level of conceptual understanding is still low due to monotonous and less contextual teaching methods, making it difficult for students to link theory with daily life. The study used a quasi-experiment method with a pretest-posttest control group design⁴. The research subject was class XII MIA2 as the experiment class. Data were collected through conceptual understanding tests (pretest and posttest), learning motivation questionnaires using the Likert scale, and observation of student engagement. The research success criterion was set when at least 85% of students achieved a score of  ≥ 70 (Minimum Mastery Criteria/KKM). The results show that the application of PBL proved capable of increasing students' conceptual understanding of redox reactions. The average conceptual understanding score significantly increased from 60 (pretest) to 80 (posttest). The percentage of learning mastery reached 88%, exceeding the research success target. In addition, the motivation questionnaire results showed an increase in the average score from the "sufficient" category to "good", especially in the indicators of curiosity and active participation. Observation also showed increased student engagement, characterized by activeness in discussions, courage in expressing opinions, and cooperation in groups.