This study aims to provide alternative solutions for 21st century learning innovations in increasing student learning activity. Where the 21st century requires students to have skills and critical thinking skills, communication, collaboration, and creativity. Relevant learning to increase student learning activity is learning that is based on constructivist understanding through a student-centered learning approach, one of which is the game-based learning model. The research method used in this research is descriptive qualitative research method. The data collected in this study include: observation results, interview results, documentation, and field notes. Data analysis refers to analytical techniques according to Miles, Huberman & Saldana (2014), namely using four stages of data analysis, namely data collection, data reduction, data presentation, and data verification or drawing conclusions. The results of this study indicate that the use of game-based learning models as innovative learning models of the 21st century provides a major role in increasing student learning activity. The potential for using games that can be integrated into the learning process is enormous. The activeness of student learning by using the game-based learning model applied in class X MAS Al-Khairiyah Pipitan Serang can be seen from the active involvement of students in the game, the courage to answer questions, express opinions, and meet the challenges of the game by collaborating with their team groups, being involved in activities solving problems both individually and in groups, constructing understanding independently, and reflecting on the learning activities that have been implemented. Based on these findings it can be understood that integrating games into a learning process through game-based learning is able to prepare students to face the challenges and skills needs of the 21st century.