2024 ASEE Annual Conference & Exposition

This complete research paper details our analysis of the effect of students’ pathways to a CS2 course on their project scores, exam scores, and final grades in the CS2 course.

Many institutions of higher learning have a standard multi-course sequence that covers the fundamentals of computer science/programming. The general introductory course is usually referred to as "CS1" in the literature; the second course usually covers data structures and is referred to as "CS2" in the literature.

The CS2 course at a large, midwestern research university has four options for a student to meet the CS1 prerequisite: credit for a college-level CS1 course at the home institution, transfer credit for a college-level CS1 course at different institution, a diagnostic test for competency, and AP credit (score of 5) for placing out of the CS1 course prerequisite requirement. These prerequisite options can represent four fundamentally different paths for students to take, and we wished to empirically verify students pursuing each pathway are sufficiently prepared to succeed in CS2 and identify any salient difference between outcomes in CS2 dependent on pathway.

Our institution historically did not provide a mechanism for students to use AP credit to place out of CS1 as it was assumed that the high school AP courses did not sufficiently prepare students for the rigors of a CS2 course taken in their first semester in college. However, as more students enrolled with significant programming experience in high school, and as more students ceased to be challenged in the CS1 courses, the path for accepting AP credit was formalized starting in the Fall 2019 semester, such that students who earned a 5 on the AP test could enter CS2 directly. This research was motivated in part by a desire to analyze whether students who enter CS2 via the AP credit path struggle more than, less than, or about the same as students entering via a college-level CS1 course.

Our assessment of student success was based on programming project scores, exam performance, and overall letter grades across seven years' worth of data (13,000+ total students). Our results show that across all metrics, students entering via the AP pathway generally perform significantly better than students entering via our traditional CS1 courses. Students who receive transfer credit for a CS1 course perform comparably to students who took a CS1 course in-house. Both alternative pathways have particularly low failure rates.