Cite as: Samsudin, M. A., Nurulazam Md Zain, A., Jamali, S. M., & Ale Ebrahim, N. (2017). Physics Achievement in STEM PjBL: A Gender Study. The Asia Pacific Journal of Educators and Education, 32. Physics Achievement in STEM PjBL: A Gender Study Mohd Ali Samsudin a , Ahmad Nurulazam Md Zain a , Seyedh Mahboobeh Jamali* a , and Nader Ale Ebrahim b a School of Educational Studies (PPIP), Universiti Sains Malaysia, Penang, Malaysia b Centre for Research Services, IPPP, University of Malaya, Malaysia *Corresponding author: Email: Mahjamali@Gmail.com Abstract Today's learners will face increasing global competition for college entrance and jobs after graduation. They need to succeed in work, life and citizenship, as well as skills that are necessary for 21 st century. Teaching and learning’s in the 21 st century has to put the emphasis on the 4Cs, collaboration, critical thinking, creativity, and communication in the gender equality environments. Science, Technology, Engineering, and Math (STEM) Project Based Learning (PjBL) provides students to learn 4Cs skills. However, the role of gender in STEM PjBL is not clear well. So, this experimental study, run a project within an experimental group of 50 students and compare with another 57 students in the control group by employing Mixed-Design ANOVA, to evaluate changes in achievement performance differences between the genders?. We observe there were not significant differences in performance of girls and boys in the high school by running a project and measuring students’ achievement. Future study should cover the effect of gender differences on the STEM PjBL teaching method in the high school for preparing students for 21 st century challenges in a broad range. Keywords 21 st century skills, Enhance teaching and learning, Gender differences, Physics education, Achievements INTRODUCTION The goal of teaching and learning for 21 st century is to find effective teaching methods and create a curriculum according to the 21 st century requirements (Holubova, 2008). In the last few decades, many reform initiatives have shaped teaching and learning in science, technology, engineering and mathematics (STEM) disciplines (Asghar, Ellington, Rice, Johnson, & Prime, 2012). These reform efforts include a shift from teaching students to remember and execute isolated facts and skills, to having students experience learning as scientists, engineers and mathematicians do (Asghar et al., 2012; NCTM, 2000). Reform efforts within each of the STEM disciplines have focused on such strategies as inquiry learning (Minstrell, 2000), project-based