CodeTailor: Personalized Parsons Puzzles are Preferred Over AI-Generated Solutions to Support Learning

Programming can be challenging for novices, and it is difficult to provide high-quality, comprehensive, and timely support at scale. Generative AI and its products, like ChatGPT, can create a solution for most introductory programming problems. However, students may become overly reliant on these tools for quick code generation and homework completion, which might cause reduced engagement and limited learning. In this work, we present CodeTailor, a system that leverages large language models (LLMs) while still encouraging students' cognitive engagement. CodeTailor provides a personalized Parsons puzzle to support struggling students. In a Parsons puzzle, students place mixed-up code blocks in the correct order to solve it. A technical evaluation with 800 incorrect student code demonstrated that CodeTailor can efficiently create high-quality (correct, personalized, and concise) Parsons puzzles for students. In a within-subjects experiment with 18 novice programmers, students rated using CodeTailor as more engaging, and they recalled more newly acquired elements from the supported practice in the posttest after using CodeTailor, compared to when they simply received an AI-generated solution. In addition, most students preferred to use CodeTailor over receiving an AI-generated solution to support learning. Qualitative observations and interviews also provided evidence for the benefits of CodeTailor, including emphasizing thinking about solution construction, fostering continuity in learning, promoting reflection, and boosting student confidence. We conclude by suggesting future design ideas for applying generative AI to facilitate active learning opportunities and minimize over-reliance.