This document provides an overview of metacognition and learner-centered psychological principles. It begins by defining metacognition as "thinking about thinking" and awareness of one's own learning processes. It then describes three categories of metacognitive knowledge and strategies to develop metacognition in students. The document also outlines 14 learner-centered psychological principles divided into cognitive/metacognitive, motivational/affective, developmental/social, and individual differences factors that influence learning. Finally, it compares differences between novice and expert learners and their use of metacognitive strategies.