The relative impact on students of small group instruction versus individualized instruction and the impact of intensive training consulting with teachers around an innovative instructional approach on subsequent use of that approach were investigated. A large-scale 10-week experiment involving 57 classes and 19 teachers in a 2 x 2 quasi-experimental design was conducted with 1,187 students involved in seventh and eighth grade language arts classes. The small group instructional approach created greater achievement on a treatment-specific measure of language arts skills and a marginally positive effect on student self-concept regarding peer relationships. (Although data was collected in 1976 for this study, the review of the literature dates through 1979.) (Author)