<![CDATA[ABSTRACT: Collaboration and Critical Thinking skills are included in the 4C skills demands in the 21st century. Collaboration skills are the ability to work effectively, appreciate diversity in a team, demonstrate flexibility, contribute to achieving common goals while critical thinking skills are the ability to analyze information, evaluate arguments, and make decisions. The purpose of this study was to describe collaboration skills, analyze students' critical thinking skills, and describe students' responses after carrying out learning activities. This study includes quantitative descriptive research with a One Group Pre-test and Post-test Design. The research sample was 2 repetition classes, each with 25 students in grade X of SMA Kartika IV-3 Surabaya. The research was conducted in January - February 2025. The research instruments were observation sheets, test questions, and questionnaires. Data were analyzed using simple statistics in the form of averages and percentages. The correlation between the ecosystem LKPD based on the collaborative learning model and students' critical thinking skills used the Pearson correlation test. The results showed that the average gain-score in the high category was 1 and had a positive correlation of 0.737. The average collaborative skills of students showed level 4 with a high level and student responses showed a very good category of 97.80%. Thus, it can be concluded that the ecosystem LKPD based on the collaborative learning model is effective for the collaboration and critical thinking skills of class X SMA students. Keywords: Collaborative learning, Collaboration, Critical thinking, Ecosystem ABSTRAK: Keterampilan Collaboration dan Critical Thinking termasuk tuntutan keterampilan 4C pada abad ke-21. Keterampilan kolaborasi merupakan kemampuan untuk bekerja secara efektif, menghargai keragaman dalam tim, menunjukkan fleksibilitas, berkontribusi demi mencapai tujuan bersama sedangkan keterampilan berpikir kritis merupakan kemampuan untuk menganalisis informasi, mengevaluasi argumen, dan mengambil keputusan. Tujuan penelitian ini adalah mendeskripsikan keterampilan kolaborasi, menganalisis keterampilan berpikir kritis peserta didik, dan mendeskripsikan respons peserta didik setelah melakukan kegiatan pembelajaran. Penelitian ini termasuk penelitian deskriptif kuantitatif dengan desain One Group Pre-test and Post-test Design. Sampel penelitian yaitu 2 kelas pengulangan masing-masing 25 peserta didik kelas X SMA Kartika IV-3 Surabaya. Penelitian dilaksanakan pada bulan Januari – Februari 2025. Instrumen penelitian berupa lembar observasi, soal tes, dan angket. Data dianalisis menggunakan statistik sederhana berupa rata-rata dan persentase. Korelasi antara LKPD ekosistem berbasis model collaborative learning dan keterampilan berpikir kritis peserta didik menggunakan uji korelasi Pearson. Hasil penelitian menunjukkan bahwa rata-rata gain-score dalam kategori tinggi sebesar 1 dan berkorelasi positif sebesar 0,737. Rata-rata keterampilan kolaborasi peserta didik menunjukkan level 4 dengan tingkat tinggi dan respons peserta didik menunjukkan kategori sangat baik sebesar 97,80%. Dengan demikian, menyimpulkan bahwa LKPD ekosistem berbasis model collaborative learning efektif terhadap keterampilan kolaborasi dan berpikir kritis peserta didik kelas X SMA. Kata kunci: Collaborative learning, Kolaborasi, Critical thinking, Ekosistem]]>
