EDUCATIONAL PSYCHOLOGY HAS CHANGED SIGNIFICANTLY OVER THE 20TEH CENTURY. EARLY INVESTIGATIONS OF CHILDREN AS LEARNERS AND IMPACT OF DIFFERENT KINDS OF TEACHING APPROACHES WERE LARGELY CHARACTERIZED BY ATTEMPTS TO IDENTIFY GENERAL AND CONSISTENT CHARACTERISTICS. THE APPROACHES USED VARIED CONSIDERABLY. JEAN PIAGET, FOR EXAMPLE, RECORDED THE DEVELOPMENT OF INDIVIDUALS IN DETAIL, ASSESSING CHANGES WITH AGE AND EXPERIENCE. OTHERS, SUCH AS ROBERT GAGNE, FOCUSED ON THE NATURE OF TEACHING AND LEARNING ATTEMPTING TO LAY DOWN TAXONOMIES OF LEARNING OUTCOMES. ALFRED BINET AND CYRIL BURT WERE INTERESTED IN METHODS OF ASSESSING CHILDREN'S CONSIDERED TO BE OF HIGH OR LOW GENERAL INTELLIGENCE. THIS WORK LED TO PRODUCTIVE RESEARCH WHICH REFINED THE THEORIES OF DEVELOPMENT, LEARNING INSTRUCTION, ASSESSMENT, AND EVALUATION, AND BUILT UP AN INCREASINGLY DETAILED PICTURE OF HOW STUDENTS LEARN.