Amount and distribution of study in a personalized instruction course and in a lecture course

The rapid proliferation of courses based on Keller's Personalized System of Instruction (PSI) calls for a prompt evaluation of the relative costs involved in PSI and more traditional forms of college instruction. To determine the cost in student time required by a course taught with PSI relative to lecture, students did their studying in a special Study Center where course materials could be used but not removed. Students in the PSI section spent an average of about 50% more time in the Study Center (46 hr) than did students in the lecture section (30 hr), but that difference was made up by the lecture students spending an average of 20 hr attending lectures. Thus, total preparation time was about the same. PSI students scored slightly higher on common course exams, and while college entrance exam scores correlated highly with course exam scores, Study Center time was reliably related to course exam score only for PSI students. An analysis of the study records of individual students revealed that PSI produced fairly regular patterns of study by all students, while lecture students varied greatly in their patterns.