Two areas of research were explored in this meta-analysis: comparison of inductive versus deductive teaching approachs, and the use of advance organizers. This study involved the coding of 128 characteristics for 39 studies which spanned the period from 1957 through 1980. The coding variables included 57 which were concerned with features of the treatment while 12 were concerned with outcome attributes. Aspects such as research methodology, sample characteristics, and instructional experiences were examined quantitatively in terms of their relationships to the treatment effects through the use of a common metric for all studies. Mean effect sizes were calculated and reported.