<![CDATA[The low communicative rationality of students in controversial history learning is often caused by the lack of argumentative dialogue spaces in the classroom. This study aims to analyze the differences in students' communicative rationality skills between those taught using the Value Clarification Technique (VCT) model and Problem-Based Learning (PBL), as well as to measure the magnitude of the VCT model's influence in assessing the controversial history of Romusha. This quantitative research utilized a quasi-experimental method with a Non-Equivalent Control Group Design. The sample was selected via purposive sampling, establishing class XI.3 (31 students) as the experimental group using the VCT model and class XI.1 (29 students) as the control group using the PBL model at SMA Ta'miriyah Surabaya. Data were collected through a triangulation of quantitative data collection methods, namely a self-assessment questionnaire as the primary instrument and a structured observation sheet as supporting data, to strengthen the validity of measuring communicative rationality. The Independent Samples T-test hypothesis testing revealed a significant difference in communicative rationality skills between the two groups, thereby accepting Ha. The effect size test using Cohen’s d yielded a value of 0.61, categorized as a medium effect. The VCT model proved effective in reinforcing Habermas's validity claims, particularly truth and comprehensibility, although the sincerity claim recorded the lowest increase due to the dynamics of students' social conformity in the field. In conclusion, the VCT model has a significant and more optimal effect on enhancing students' communicative rationality compared to the PBL model. ABSTRAK Rendahnya rasionalitas komunikatif peserta didik dalam pembelajaran sejarah kontroversial sering kali disebabkan oleh minimnya ruang dialog berbasis argumentasi di kelas. Penelitian ini bertujuan untuk menganalisis perbedaan kemampuan rasionalitas komunikatif peserta didik antara yang dibelajarkan dengan model Value Clarification Technique (VCT) dan Problem Based Learning (PBL), serta mengukur besar pengaruh model VCT dalam menilai sejarah kontroversial Romusha. Penelitian kuantitatif ini menggunakan metode eksperimen semu (quasi-experiment) dengan desain Non-Equivalent Control Group Design. Sampel dipilih melalui teknik purposive sampling, menetapkan kelas XI.3 (31 peserta didik) sebagai kelas eksperimen dengan model VCT dan kelas XI.1 (29 peserta didik) sebagai kelas kontrol dengan model PBL di SMA Ta'miriyah Surabaya. Data dikumpulkan melalui triangulasi metode pengumpulan data kuantitatif, yaitu kuesioner self-assessment sebagai instrumen utama dan lembar observasi terstruktur sebagai data pendukung, guna memperkuat validitas pengukuran rasionalitas komunikatif. Hasil uji hipotesis Independent Samples T-test menunjukkan perbedaan yang signifikan pada kemampuan komunikasi rasional antara kedua kelompok, sehingga Ha diterima. Hasil uji effect size menggunakan Cohen’s d diperoleh nilai 0,61 yang termasuk dalam kategori pengaruh sedang (medium effect). Model VCT terbukti efektif memperkuat klaim validitas Habermas, khususnya klaim kebenaran (truth) dan kejelasan (comprehensibility), meskipun klaim kejujuran (sincerity) mencatatkan peningkatan paling rendah akibat adanya dinamika konformitas sosial peserta didik di lapangan. Simpulan penelitian menunjukkan bahwa model VCT berpengaruh secara signifikan dan lebih optimal meningkatkan rasionalitas komunikatif peserta didik dibandingkan model PBL.]]>
