Project based learning is a student-centered approach where students explore real-world problems and challenges. It has the teacher acting as a facilitator while students work collaboratively to find solutions. Key characteristics include addressing issues students find meaningful, motivating advanced thinking skills, and promoting collaboration. Experts say students retain knowledge better through project based learning since they learn by doing, questioning, and critical thinking. In 21st century education, it makes school more authentic and results in deeper, self-directed learning.