Courses: This semester long activity can be employed in any communication classroom and is designed particularly to provide first-time graduate student instructors (GSIs) with a theory-based assessment tool. As such, the article is appropriate for graduate-level pedagogy classes. Objective: To introduce a theory-based, critical thinking activity…

This report results from studies that tested two variations of Bloom's decreasing variability hypothesis using performance on successive units of achievement in four graduate classrooms that used mastery learning procedures. Data do not support the decreasing variability hypothesis; rather, they show no change over time. (SM)