This action research demonstrates the answer to this question: How can literacy professors provide effective training in evaluating writing to preservice graduate education students? The study examines writing assessment instruction in the context of a literacy course required of preservice teachers seeking secondary (7-12) certification in content area instruction. Approximately half of the course is devoted to instruction in 3 areas of writing assessment: (1) theory and practice in aspects of holistic writing assessment analysis, (2) methods for designing teachable rubrics, and (3) approaches to creating and sharing written feedback. Student-participants' written responses to protocols demonstrate learning outcomes in these 3 areas along with their attitudes and the effects of their practice with an authentic set of high school students' essays. The study demonstrates the effectiveness of this assessment instruction as a part of overall effectiveness in teacher preparation programs at the graduate level.