The Middle School Study of Mainstreamed Students sought to establish a foundation for interdisciplinary research on middle school mainstreaming by merging teacher effectiveness and special education practices. The study examined teaching behaviors through macro (classroom) and micro (individual student) analyses of classroom interactions, to identify those interactions which produce high levels of teacher and learner performance. An experimental group of middle school social studies teachers participated in an inservice program on effective use of classroom time, consistency management, and interventions for low-achieving and mainstreamed students. Results of the first year's research indicated that teachers known to be effective at the macro level were also found to be effective, high-impact teachers at the micro level. In the second year, the sample pool and research design were modified, and initial analyses of second year data support the first year findings. (JDD)