Tokkatsu: Initiating students' collaborative activities in lesson study piloting school. Objectives: This study aims to look at the best practices of tokkatsu implementation in familiarizing students' collaborative learning activities. Methods: This qualitative descriptive study was conducted at SD Muhammadiyah 4 Batu during July-December 2018 involving 31 subjects in grade V. The method was divided into four stages, including building basic student relations, relationship development, student learning methods, and integration of learning patterns into subjects. Data collection using observation and interview techniques, then analyzed qualitatively. Findings: The results showed that tokkatsu was able to initiate and stimulate students collaboration. Strengthening collaboration is carried out by reformulating ways of learning and habit of asking questions as the foundation of collaborative learning. Conclusion: The results of this study are used as a basis for improvement and strengthening of lesson study activities in schools.