A two page checklist was developed to assist educators in predicting the success or failure of children in open classrooms. The checklist was based on the results of a survey of ninety-one open classroom teachers who were asked to list the characteristics of successful and unsuccessful children in open classrooms. Content validity was established by having a second group of classroom teachers determine the observability of selected classroom behaviors and having faculty members match observable behaviors to children's characteristics. Concurrent validity is being established by comparing observer results to teacher ratings. Observations in the first trial run showed that teacher and researcher checklist results disagreed on an average of only seven percent of the items per child; however, each researcher checked only those behaviors that were clearly observable during the observation period. Initial data analysis to establish interrater reliability showed observer agreement to be 85 percent. (Author/BW)