Using instructional variables identified by the literature as important in predicting classroom achievement, a bi-polar rating scale was designed to assess the structure of instruction in resource rooms. The data for 158 elementary school children in four school districts were analyzed. The scale evidenced good reliability, both in terms of inter-observer agreement and internal consistency measures. Factor analysis of the scale identified one factor consisting of 9 of the 12 scale variables. Teacher use of instructional structure and implications for educational practice are discussed. (Author)