Verbal praise, a type of external reward addressed in many theories of motivation, has often been recognized as an important mediator in the development of students' motivation in the classroom. However, the lack of consistently replicated findings regarding students' reactions to verbal praise, combined with the paucity of research on post-secondary students, prompted the current investigation. Using an experimental design, the author found that college students exposed to well-administered verbal praise by a professor spent significantly more time doing homework than did students who received no verbal praise. Characteristics of effective verbal praise that contributed to the results, the potential usefulness of verbal praise as an enhancer of student motivation, and directions for future research are discussed.