The document outlines 14 learner-centered psychological principles developed by the American Psychological Association, which focus on internal psychological factors influencing learning. These principles encompass cognitive, motivational, developmental, social, and individual difference factors, and are designed to apply to various educational stakeholders, including students, teachers, and parents. Effective learning is characterized by active engagement, personal goal setting, and the integration of new knowledge with prior understanding, while acknowledging the significant influence of external environmental factors.