Medical residents, frontline clinical educators, must be competent teachers. Typically, resident teaching competence is not assessed through any other means than gleaning learner's comments. We developed, evaluated, and integrated into our annual objective structured clinical examination a resident teaching skills assessment using “standardized” students. Faculty observers rated residents using a customized 19-item rating instrument developed to assess teaching competencies that were identified and defined as part of our project. This was feasible, acceptable, and valuable to all 65 residents, 8 students, and 16 faculty who participated. Teaching scenarios have potential as reliable, valid, and practical measures of resident teaching skills.