1. Division of content material into smaller units or modules requiring spaced rather than massed practice 2. Reduced reliance on lectures and instead, the extensive use of written study guides which define the material to be learned through provision for definition of behavioral objectives and study questions 3. Requirement of mastery for each unit and repeated, unpenalized testing until mastery is demonstrated 4. Use of advanced students as tutors and administrators of unit mastery quizzes 5. The chief difference between traditional methods of instruction and PSI is that in traditional methods, students are given the same instruction and allowed the same amount of time in which to prepare for examinations scheduled by the instructor.
Differences occur among students in the knowledge and skills they have acquired.
These differences, reflected in test performance, are the source of student evaluation. Thus time is fixed while performance is allowed to vary. In PSI, the knowledge and skills acquired by each student is fixed by the instructor in terms of a mastery criterion. Students are allowed differing amounts of time and study techniques to reach the fixed criterion. Thus performance criteria are fixed while time is allowed to vary.