As many as 1 in 5 youth in the United States experience social, emotional, and behavioral problems. However, many students with mental health concerns are unidentified and do not receive adequate care. The purpose of this study was to evaluate the factor structure, measurement invariance, and the concurrent and predictive validity of the Early Identification System--Student Report (EIS-SR), a screener for social, emotional, and behavioral problems, using a sample of over 5000 students from Grades 3 to 5. The EIS-SR was developed by using extant literature on the risk indicators that lead to social, emotional, and behavioral challenges among children and youth. As expected, seven subscales were identified as having adequate factor loadings. Furthermore, the measure was determined to be invariant across grade level (n = 5005), gender (n = 5005), and between Black and White students (n = 1582). The concurrent validity of the Internalizing Behavior, Attention and Academic Issues, Emotion Dysregulation, and School Disengagement subscales was supported by correlations with comparable subscales of the Behavior Assessment System for Children--3rd Edition (BASC-3; n = 382). Additionally, the EIS-SR subscales administered in the fall of the school year were predictive of important outcomes in spring, including attendance (n = 4780), disciplinary referrals (n = 4938), bully victimization (n = 4670), math academic achievement scores (n = 4736), and reading (n = 4772) academic achievement scores. The EIS-SR holds promise as a feasible and technically adequate screening tool for use in elementary schools.