UC San Diego

Instructors and institutions tend to treat students who have fulfilled their prerequisites for a course as if they are all equally well-prepared. Recent work in computing has shown that a substantial proportion of students are entering later courses with low prerequisite course proficiency, possibly hurting student outcomes. This dissertation explores (1) the extent of low prerequisite course proficiency throughout our CS curriculum, (2) the impacts of low proficiency on student outcomes, with a focus on students typically underrepresented in computing, and (3) possible causes leading to low proficiency as well as possible reasons why students are able to succeed in courses despite entering underprepared.

Regarding extent: we find that a substantial proportion of students, across multiple courses, enter courses with low prerequisite proficiency.

Regarding impacts: encouragingly, we find that student grades in prior courses are predictive of prerequisite proficiency coming into a course and student success in the course. We also find a relationship between students' incoming proficiency and their performance in the course. This suggests that the low prerequisite proficiency may be negatively impacting student outcomes. In terms of subpopulations, there is a disproportionate impact on students typically underrepresented in computing.

Regarding causes: in contrast with previous research, we find no harmful effects on prerequisite proficiency due to the passage of time or taking alternative prerequisites. In terms of instructor expectations, we find that instructors overestimate students’ incoming prerequisite proficiency. Furthermore, we find that many instructors believe prerequisites are not fulfilling their purpose. They cited various reasons including the number of conflicting pressures instructors face with respect to ensuring students learn material expected for the next course (e.g., trying not to adversely impact students’ time-to-degree, being well-liked by students, and balancing the time spent on teaching with other responsibilities).