This study replicated an earlier study conducted by Tarter and Hoy (2004) in which an open systems model was used to test a series of hypotheses that explained elements of school performance. Four internal system elements (structure, individual, culture, and politics) of the school were used to explain two sets of school outcomes (student achievement and teachers' assessment of overall school effectiveness) in a sample of 110 Catholic elementary schools in one Northeastern city. Correlational and multiple regression analyses were used to test the relationships. The results of this study further confirmed the usefulness of this model in understanding the factors that contribute to quality in elementary schools. (Contains 4 tables.)