This study details development and validation efforts for a new strength-based assessment instrument: the Social-Emotional Assets and Resilience Scales, Teacher rating form (SEARS-T). A large and diverse nationwide sample of more than 1,500 teacher ratings of students in kindergarten through Grade 12 was obtained. Factor-analytic procedures revealed a robust four-factor structure. The factor scores and total score of the SEARS-T were shown to have strong internal consistency. Convergent construct validity of the SEARS-T was established through findings of significant correlations with two established strength-based rating scales. Construct validity was supported through findings of significant gender and special education classification status differences in scores. Limitations and future research needs are discussed, as are implications for research and practice in school settings. (Contains 6 tables and 1 figure.)