The APA's learner-centered psychological principles involve cognitive and metacognitive factors(the nature of the learning process, goals of the learn process, the construction of knowledge, strategic thinking, thinking about thinking, and the context of learning), motivational and affective factors(motivational and emotional influences on learning, intrinsic motivation to learn, and effects of motivation on effort) developmental and social factors(developmental influences on learning and social influences on learning), at individual differences factors(individual differences in learning, learning and diversity, and standards and assessment. .