The purpose of a prominent feature analysis is to describe the stylistic flexibility that a young writer, or a group of young writers, exhibits on a given day, with a given prompt. In prominent feature analysis, there are no guidebooks, no rubrics--just student papers and the expertise of teachers. Teachers come to the papers individually and yet work as a team, analyzing the papers but also having the advantage of multiple points of view, with the added value of rich professional conversation. All involved in the process are learning. Looking deeply into the writing of their students, teachers are not only better prepared to make sound instructional decisions but are also better able to articulate the quality of their students' writing abilities. What is the value of the prominent feature analysis for classroom instruction? First, there is a precise numerical score that can be used for comparative and evaluative purposes. But beyond each score is a set of rhetorical features, both positive and negative, for each student that can be used for diagnostic purposes. This information has powerful implications for long-range planning and staff development programs, but most important, for the day-to-day work of the classroom teacher and the rhetorical growth of young writers. In this article, the authors explain how identifying the most positive elements of good writing, such as voice and effective repetition, can help teachers focus on specific concepts to help student writers improve. (Contains 1 figure.)