THE OBJECTIVES OF THIS STUDY WERE TO EXAMINE THE EXCHANGE PROCESSES PREDICTING DIFFERENTIAL ALLOCATIONS OF EFFORT AMONG STUDENTS' COURSES, AND TO EXPLAIN THE RELATIONSHIPS DISCOVERED. THE INVESTIGATORS BELIEVE THAT THE FOUR EXCHANGE SYSTEMS RELEVANT TO THE EFFORT-ALLOCATIONS OF STUDENTS ARE--(1) PROFESSOR-STUDENT, (2) COURSE-STUDENT, (3) PEER-STUDENT, AND (4) EGO-EXCHANGES. IT IS PROPOSED THAT THE TWO BASIC PRESSURES OPERANT IN EXCHANGE BEHAVIOR ARE--(1) PRESSURE TO ACHIEVE AN EQUILIBRIOUS RELATION WITH THOSE WHOM WE INTERACT, AND (2) ATTEMPTS BY INDIVIDUALS TO PROFIT BY PERSONAL BEHAVIORS. DATA ON 43 VARIABLES WERE COLLECTED BY MAGNITUDE ESTIMATION PROCEDURES FROM 260 COLLEGE FRESHMEN AND 269 SENIORS. RESULTS WERE--(1) FRESHMEN WERE LITTLE INFLUENCED BY PROFESSOR CHARACTERISTICS IN THEIR WORK ALLOCATIONS, (2) AMONG SENIORS, PERSONAL CHARACTERISTICS OF THE PROFESSOR AND PERSONAL ATTENTION FROM HIM WERE SALIENT PREDICTORS, (3) THE AMOUNT OF REQUIRED WORK PREDICTED AMOUNT OF EFFORT, (4) THE DIFFICULTY OF THE COURSE PREDICTED WORK ALLOCATION AMONG FRESHMEN, (5) MORE IMMEDIATE DEMANDS OF THE COURSE HAD MORE INFLUENCE THAN REMOTE VARIABLES, (6) THE AMOUNT OF WORK EXPECTED BY PEERS WAS A SIGNIFICANT PREDICTOR, AND (7) EXPECTATIONS OF SELF INFLUENCED WORK ALLOCATION. THE STUDY PROVIDES INDUCTIVE EVIDENCE FOR THE PROPOSED THEORY OF EXCHANGE. (PH)