There are racial and ethnic disparities in use of out-of-school suspensions within the United States. The present study assessed for the presence of disproportionate suspension by race, special education status, and receipt of free or reduced cost meals using two separate metrics (risk ratios and raw differential representation); evaluated separate models of disproportionate suspension for students identified as Black, White, and Hispanic; and examined potential curvilinear associations between the proportion of the racial/ethnic group within the school population and disproportionate suspension. Aggregate data from elementary (n = 27), middle (n = 9), and high (n = 4) U.S. schools with over 105,000 students were included. Results indicated disproportionate suspension was present for Black-identified students, students in special education, and those with socioeconomic difficulties. Metrics of risk ratios and raw differential representation demonstrated somewhat different patterns in disproportionate suspension. We observed a significant curvilinear effect of the proportion of the school body identified as Black versus White on suspension practices. Students identified as White in schools with a larger White student body were more protected from suspension whereas students identified as Black were overrepresented among those suspended regardless of the student body composition. Findings suggest Black-identified students experience differential treatment in school settings and future tested models are encouraged to include more specific teacher and school administrator factors.