FWU Journal of Social Sciences, Vol 18, No.3, Fall 2024,25-34 DOI: http://doi.org/10.51709/19951272/Fall2024/3 Instrument Construction and Exploration of Students' Collaboration Skills Based on the Summated Rating Scale Rahmat Danni Universitas Negeri Yogyakarta & IAIN Syaikh Abdurrahman Siddik Bangka Belitung, Indonesia Muhammad Istiqlal and Faridah Agus Setiawati Universitas Negeri Yogyakarta, Indonesia One of the essential 21st-century skills that students must possess is the ability to collaborate. However, profiling students' collaboration skills is challenging without valid and reliable instruments. Therefore, this research aims to map the profile of students' collaboration skills using valid and reliable instruments. This study is descriptive-explorative research with a quantitative approach. The research sample included 900 Islamic Senior High School/Madrasah Aliyah students, with 150 students participating in the instrument trials and 750 serving as the primary sample in this study. The results indicate that the collaboration ability instrument is valid and reliable, as demonstrated by a loading factor value > 0.5, T-Value > 1.96, RMSEA 0.00 < 0.08, RMR 0.043, Std. RMR 0.040, GFI 0.95, AGFI 0.87, NNFI 0.97, CFI 0.98, IFI 0.98, RFI 0.97, PNFI 0.85, and a composite reliability coefficient CR=0.909 from the second-order confirmatory factor analysis. The findings show that students' collaboration skills are moderate, with an average score of 26.4, which falls within the medium category. The distribution of students' abilities is as follows: 347 students (46.3%) are classified as having moderate abilities, 207 students (27.6%) as having high skills, and 196 students (26.1%) as having low skills. Based on these results, teachers and stakeholders are encouraged to enhance students' collaboration skills through student-centred learning approaches, such as project-based learning, which can provide students with opportunities to engage and practice working together actively in the learning process. Keywords: 21st-century skills, collaboration skills, summated rating scale The rapid development of technology has impacted life in the 21st century. Changes in the reality of life are inevitable. Education plays a crucial role in shaping individuals to meet the demands of the current era. Therefore, the education system must equip students with knowledge, character, and skills aligned with the 21st century. (Malik et al., 2023). Trilling and Fadel (2009) state that there are four essential skills that students must develop in the 21st century: critical thinking, collaboration, communication, and creativity. This aligns with the Project to strengthen the Pancasila student profile (P5) implemented in Indonesia. The values instilled in the Project to strengthen the Pancasila student profile (P5) include being faithful and devoted to God Almighty, having noble character, being globally diverse, working together, being independent, thinking critically, and being creative. (Maisyaroh et al., 2023; Septinaningrum et al., 2022; Wulandari et al., 2023). In the era of globalisation, collaboration skills have become one of the key competencies students need to succeed in both the workplace and everyday life. 21st-century education emphasises the importance of collaboration skills, as modern work environments require individuals who can work independently and collaborate with others to achieve common goals. According to Greenstein (2012), collaboration is considered one of the essential life skills, encompassing the ability to communicate effectively, resolve conflicts, build consensus, and work in teams. Therefore, it is crucial to ensure that these skills are measured with valid and reliable instruments so that the development of collaboration skills can be both monitored and enhanced. Correspondence concerning this article should be addressed to Rahmat Danni, Doctoral Candidate in Educational Research and Evaluation at Universitas Negeri Yogyakarta, Indonesia, and Lecturer in the Department of Education at IAIN Syaikh Abdurrahman Siddik Bangka Belitung, Indonesia. Email: rahmatdanni.2023@student.uny.ac.id