This proposal describes the procedures used by a student teacher in a San Diego area twelfth grade Rhetoric and Composition class that were designed to improve the critical thinking (CT) skills of his students. Emphasis was placed on improving the CT skills of the students by incorporating researcher Richard Paul's "Elements and Standards of Reasoning" into all standards-based curriculum, which included persuasive essays on the topics of child abuse, language, gender and culture, and the value of life. Students were identified as high-range, mid-range, low-range achievers, or ELL's. The progress of each group was measured through a progressive series of rubric assessments of their writing, examining five key areas important in rhetorical composition: Clarity of Writing, Analysis of author's argument, Use of supporting information, Organization, and Grammar and Syntax. Through the introduction of this focused critical thinking training, student composition improved dramatically in all of the five key areas, among all the groups. The researcher proposes to introduce focused CT practices in a trial set of Language Arts classes within the district at large, modeled on this action research.