Using formative assessment to enhance student performance on geometric proof writing

The purpose of this research is to uncover best practices to create competent proof writers. Studies have shown the best setting to do this is in the high school geometry classroom. Throughout a yearlong study of geometry, students were exposed to theorems and their demonstrations. Despite constant exposure, students were still unable to produce their own proof of propositions. The questions then became how can an educator provide critical feedback that encourages student reasoning and develops logical argumentation skills? With the goal in mind, twenty-five students enrolled in a geometry course at Baton Rouge High School in Baton Rouge, Louisiana were given the task of replicating certain proofs in their own words. More than the students’ performance, this research focuses on the teacher’s role as a feedback source of students’ proof-writing ability. Submitted are the efforts of one educator to establish norms in the construction of geometric proof writing, provide a method of feedback in the form of a student checklist and student teacher interviews, and adapt these efforts into an evaluation tool. The research will show students’ original writing, teacher feedback, final product, and the evaluation results in the hopes of establishing best practices to increase student performance on proof writing tasks