A Case Study: Using STACK Questions in an Engineering Module

Computer-assisted assessment (CAA) can give immediate feedback to students, which leads to better learning. This paper presents a case study of using STACK in a third-year mathematical engineering module. STACK is an advanced computer-assisted assessment tool that can automatically mark mathematical equations. STACK is a Moodle plugin that allows students to enter mathematical formulae as answers. It checks if the student's answer is mathematically equivalent to the model answer and can provide hints to the student. Students attempt the same question several times, getting hints with each incorrect attempt. STACK questions were used in three different settings: short practice problems that students did at home; long tutorial sessions that students did in class; a two-hour semester test. This paper reflects on the use of STACK during a semester. It summarises feedback from students that were collected during interviews, it discusses systemic challenges when implementing STACK questions, and it looks at the mark distribution of STACK-based questions. Overall, STACK proved to be a useful formative assessment tool. The immediate feedback allowed all the students to solve all the tutorial problems before the end of the tutorial session. The downside to using STACK during the semester test was that students were became anxious because they immediately knew when their answers were wrong.