Exploring and Influencing Teacher Grading for Block-based Programs through Rubrics and the GradeSnap Tool

This article examines the grading process and profiles of secondary computer science teachers as they assess block-based student programming submissions. Through an iterative design process, we have created a new tool, Gradesnap, which streamlines how teachers can open, review, and evaluate student submissions within the same interface. Our study compares teachers’ grading processes using the different assessment formats, so that we can understand how their grading processes can be augmented or supported to reduce ’pain points’ and to enable teachers to provide more constructive and formative feedback for students. We use a case study approach to examine the experiences and outcomes of four secondary computer science teachers with varied teaching and assessment experience, when grading as usual, grading with a rubric, and grading with GradeSnap. Our study shows that when participants use GradeSnap, they are able to give supportive comments to lower performing and borderline students who need critical feedback to better understand misconceptions. We also discovered that the different grading processes provided a vehicle for reflection for some teachers in understanding their grading goals and how they enact them. This research is the first to examine teacher grading processes for computer science, and highlights the need for teacher preparation and support for providing programming feedback and assessment.