ABSTRAK Penelitian ini bertujuan untuk meningkatkan keterampilan kolaborasi murid melalui penerapan model pembelajaran kooperatif tipe Student Teams Achievement Divisions (STAD) dalam pembelajaran IPAS materi Bentang Alam Daerahku. Penelitian ini menggunakan metode Penelitian Tindakan Kelas (PTK) dengan model Kemmis dan McTaggart yang dilaksanakan dalam dua siklus, meliputi perencanaan, tindakan, observasi, dan refleksi. Subjek penelitian berjumlah 25 murid kelas IV di salah satu sekolah dasar di Kota Surabaya. Data dikumpulkan melalui observasi dan dokumentasi, kemudian dianalisis menggunakan pendekatan deskriptif kuantitatif dan kualitatif. Keterampilan kolaborasi diamati melalui lima indikator, yaitu partisipasi aktif, pembagian tanggung jawab, komunikasi, menghargai pendapat, dan membantu anggota kelompok. Hasil penelitian menunjukkan bahwa rata-rata persentase keterampilan kolaborasi meningkat dari 52,4% pada Siklus I menjadi 83,8% pada Siklus II, atau naik sebesar 31,4 poin persentase. Peningkatan terjadi pada seluruh indikator, dengan peningkatan terbesar pada pembagian tanggung jawab, dari 45% menjadi 88%. Perbaikan tindakan pada Siklus II meliputi pembagian peran yang lebih sistematis, pengembangan kuis Memories, Recall, Examine (MRE) menjadi 15 soal per kelompok, serta pemberian penghargaan kelompok. Rata-rata keterampilan kolaborasi pada Siklus II telah melampaui kriteria keberhasilan sebesar 75%. Dengan demikian, perbaikan penerapan STAD menunjukkan peningkatan keterampilan kolaborasi murid dalam konteks kelas yang diteliti. ABSTRACT This study aims to improve students’ collaboration skills through the application of the Student Teams Achievement Divisions (STAD) cooperative learning model in IPAS lessons on the topic “The Landforms of My Region.” This study used the Classroom Action Research (CAR) method based on the Kemmis and McTaggart model, conducted in two cycles comprising planning, action, observation, and reflection. The research subjects consisted of 25 fourth-grade students at an elementary school in Surabaya. Data were collected through observation and documentation, then analyzed using both quantitative and qualitative descriptive approaches. Collaboration skills were assessed based on five indicators: active participation, sharing of responsibilities, communication, respecting others’ opinions, and helping group members. The research findings show that the average percentage of collaboration skills increased from 52.4% in Cycle I to 83.8% in Cycle II, representing an increase of 31.4 percentage points. Improvements were observed across all indicators, with the largest increase seen in the sharing of responsibilities, which rose from 45% to 88%. Improvements in Cycle II included a more systematic division of roles, expanding the Memories, Recall, Examine (MRE) quiz to 15 questions per group, and awarding group prizes. The average collaboration skill score in Cycle II exceeded the 75% success criterion. Thus, improvements in the implementation of STAD demonstrated an increase in students’ collaboration skills within the context of the classroom under study.