Web-based grading of symbolic answers

This paper describes a system in which the computer algebra system Maple running on a remote server is used to check the correctness of symbolic answers submitted via the World Wide Web. The goal is to have a computer grade the kinds of symbolic algebraic, trigonometric, and calculus expressions that arise naturally in engineering and scientific applications rather than just numerical or multiple-choice options. The ability to grade symbolic answers can be used synchronously (on-line quizzes or exams under monitored conditions) or asynchronously (e.g., homework, tutorials, or readiness tests) for a broad range of quantitative courses and levels. A database keeps extensive, detailed records of student performance. This paper describes a system for symbolic grading via a Web browser. After giving the background and a brief overview of the system, it presents two simple computer-gradable problems and the steps used to grade an illustrative problem. The paper concludes with a brief summary of the work in progress toward a system that can be used for a variety of Web-based grading activities over a broad spectrum of on-site or remote quantitative courses.