An Analysis of Using Many Small Programs in CS1

Modern program auto-graders enable new CS1 approaches. Instructors can easily create new assignments, with students receiving immediate score feedback and resubmitting assignments. With such auto-graders, one approach assigns many small programs (MSPs) each week instead of one large program (OLP). Earlier research showed MSPs in CS1 yielded happier students and better grades. Our university and other schools have switched to MSPs in CS1. This paper addresses common questions about MSPs. We analyzed submissions for a 76-student section of our MSP CS1 course. Given 7 MSPs per week each worth 10 points, students needed 50 points for full credit. Students averaged 17 minutes per MSP and 120 minutes per week. Given 7 days, students on average started 2.2 days ahead of the due date, with 37% starting at least 3 days ahead. 40% of students exceeded the required 50 points per week (no extra credit was given). 50% of students "pivoted" -- switching to another program before completing the previous one. 54% used MSPs to study for exams. Students used MSPs in ways beneficial to their learning and stress reduction: spending sufficient time, completing more than necessary, preparing for exams, and pivoting to avoid getting stuck. A common concern is that MSP CS1 students will do poorly in a CS2 using OLPs. We analyzed 5 quarters of CS2 and found MSP students do fine (in fact slightly better). These results encourage use and refinement of MSPs in CS1 and other courses.