From Bugs to Breakthroughs: Novice Errors in CS2

Background: Programming is a fundamental skill in computer science and software engineering specifically. Mastering it is a challenge for novices, which is evidenced by numerous errors that students make during programming assignments. Objective: In our study, we want to identify common programming errors in CS2 courses and understand how students evolve over time. Method: To this end, we conducted a longitudinal study of errors that students of a CS2 course made in subsequent programming assignments. Specifically, we manually categorized 710 errors based on a modified version of an established error framework. Result: We could observe a learning curve of students, such that they start out with only few syntactical errors, but with a high number of semantic errors. During the course, the syntax and semantic errors almost completely vanish, but logical errors remain consistently present. Conclusion: Thus, students have only little trouble with learning the programming language, but need more time to understand and express concepts in a programming language.