Inconsistencies in the use of terminology to describe instructional treatments, confounding of discovery and expository methods with other aspects of instruction, and inconsistencies in defining independent and dependent variables within and between studies have all contributed to the lack of definitive conclusions about the effectiveness of different instructional methods. The purpose of this study was to compare the effectiveness of three instructional methods, i.e., expository, discovery, and a modified form of discovery, Component Display Theory, which incorporated the rule given in the expository lesson using a theoretical paradigm for analyzing the components of instruction. The subjects were 50 third-graders from Syracuse, New York, and a concept taken from beginning set theory in conceptual mathematics was selected as the task. While none of the instructional treatments proved to be significantly better on the overall test incorporating both application and transfer subscales, a few differences did emerge through analysis of the subscale results. The findings indicated that explicitly providing a generality, whether at the beginning or at the end of a lesson, will facilitate performance on applying that generality. A 15-item reference list is provided. (RP)