関連ワード:  what is problem based learning pbl    what is problem based learning and project based learning    what is a key feature of problem based learning pbl )    what is the primary focus of problem based learning pbl )    problem based learning pbl theory    problem based learning pbl approach    problem based learning pbl in a professional context typically involves    problem based learning pbl examples    problem based learning pbl ppt    problem-based learning (pbl) maastricht university