Argues that a controlled study of Supplemental Instruction (SI) sessions in college chemistry showed that participants benefited from SI sessions to an extent that cannot be explained only by their higher levels of motivation. Reports that SI includes services such as one-on-one, drop-in, and group tutoring. (Contains 11 references.) (AUTH/NB)

Between 40% and 50% of Chemistry 103 registrants at the University of Maryland at College Park earn D, F, or W grades. Registrants for Chemistry 103 were randomly selected to participate in a pre-course refresher consisting of listening to as many as seven audio-tutorial tapes on the basic concepts and calculations of chemistry. Records were kept…