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  1. Free, publicly-accessible full text available August 3, 2023
  2. As computing courses become larger, students of minoritized groups continue to disproportionately face challenges that hinder their academic and professional success (e.g. implicit bias, microaggressions, lack of resources, assumptions of preparatory privilege). This can impact career aspirations and sense of belonging in computing communities. Instructors have the power to make immediate changes to support more equitable learning, but they are often unaware of students' challenges. To help both instructors and students understand the inequities in their classes, we developed StudentAmp, an interactive system that uses student feedback and self-reported demographic information (e.g. gender, ethnicity, disability, educational background) to show challenges and how they affect students differently. To help instructors make sense of feedback, StudentAmp ranks challenges by student-perceived disruptiveness. We conducted formative evaluations with five large college computing courses (150 - 750 students) being taught remotely during the COVID-19 pandemic. We found that students shared challenges beyond the scope of the course, perceived sharing information about who they were as useful but potentially dangerous, and that teaching teams were able to use this information to consider the positionality of students sharing challenges. Our findings relate to a central design tension of supporting equity by sharing contextualized information about students whilemore »also ensuring their privacy and well-being.« less
    Free, publicly-accessible full text available March 30, 2023
  3. Background and Context: Current introductory instruction fails to identify, structure, and sequence the many skills involved in programming. Objective: We proposed a theory which identifies four distinct skills that novices learn incrementally. These skills are tracing, writing syntax, comprehending templates (reusable abstractions of programming knowledge), and writing code with templates. We theorized that explicit instruction of these skills decreases cognitive demand. Method: We conducted an exploratory mixed-methods study and compared students’ exercise completion rates, error rates, ability to explain code, and engagement when learning to program. We compared material that reflects this theory to more traditional material that does not distinguish between skills. Findings: Teaching skills incrementally resulted in improved completion rate on practice exercises, and decreased error rate and improved understanding of the post-test. Implications: By structuring programming skills such that they can be taught explicitly and incrementally, we can inform instructional design and improve future research on understanding how novice programmers develop understanding.
  4. Prior work on novice programmers' self-regulation have shown it to be inconsistent and shallow, but trainable through direct instruction. However, prior work has primarily studied self-regulation retrospectively, which relies on students to remember how they regulated their process, or in laboratory settings, limiting the ecological validity of findings. To address these limitations, we investigated 31 novice programmers' self-regulation in situ over 10 weeks. We had them to keep journals about their work and later had them to reflect on their journaling. Through a series of qualitative analyses of journals and survey responses, we found that all participants monitored their process and evaluated their work, that few interpreted the problems they were solving or adapted prior solutions. We also found that some students self-regulated their programming in many ways, while others in almost none. Students reported many difficulties integrating reflection into their work; some were completely unaware of their process, some struggled to integrate reflection into their process, and others found reflection conflicted with their work. These results suggest that self-regulation during programming is highly variable in practice, and that teaching self-regulation skills to improve programming outcomes may require differentiated instruction based on students self-awareness and existing programming practices.
  5. Formative assessments can have positive effects on learning, but few exist for computing, even for basic skills such as program tracing. Instead, teachers often rely on overly broad test questions that lack the diagnostic granularity needed to measure early learning. We followed Kane's framework for assessment validity to design a formative assessment of JavaScript program tracing, developing "an argument for effectiveness for a specific use." This included: 1) a fine-grained scoring model to guide practice, 2) item design to test parts of our fine-grained model with low confound-caused variance, 3) a covering test design that samples from a space of items and covers the scoring model, and 4) a feasibility argument for effectiveness for formative use (can target and improve learning). We contribute a distillation of Kane's framework situated for computing education, and a novel application of Kane's framework to formative assessment of program tracing, focusing on scoring, generalization, and use. Our application also contributes a novel way of modeling possible conceptions of a programming language's semantics by modeling prevalent compositions of control flow and data flow graphs and the paths through them, a process for generating test items, and principles for minimizing item confounds.
  6. Tests serve an important role in computing education, measuring achievement and differentiating between learners with varying knowledge. But tests may have flaws that confuse learners or may be too difficult or easy, making test scores less valid and reliable. We analyzed the Second Computer Science 1 (SCS1) concept inventory, a widely used assessment of introductory computer science (CS1) knowledge, for such flaws. The prior validation study of the SCS1 used Classical Test Theory and was unable to determine whether differences in scores were a result of question properties or learner knowledge. We extended this validation by modeling question difficulty and learner knowledge separately with Item Response Theory (IRT) and performing expert review on problematic questions. We found that three questions measured knowledge that was unrelated to the rest of the SCS1, and four questions were too difficult for our sample of 489 undergrads from two universities.
  7. About half of recent computer and information science graduates attended community college at some point. Prior work on transfer students in general suggests that the transfer process can engage people from underrepresented communities, but can also be academically and socially "shocking". However, we know little about the experiences of transfer students in computer science in particular. We used the Laanan-Transfer Student Questionnaire (L-TSQ) to survey 25 transfer students and 135 native (non-transfer) students and conducted follow-up interviews with 8 transfer students attending a large public 4-year university in a city with significant technology industry presence. We found that while transfer students were more diverse demographically, the support of the university for transfer student orientation tended to mitigate social shocks of transferring. This did not, however, eliminate gaps in academic performance. These findings suggest that there are other non-social factors that influence academic performance that CS programs must support to equitably engage students who transfer.