Spaced Retrieval Practice Imposes Desirable Difficulty in Calculus Learning

Abstract After being taught how to perform a new mathematical operation, students are often given several practice problems in single set, such as homework assignment or quiz (i.e., massed practice). An alternative approach is distribute across multiple homeworks quizzes, increasing the temporal interval between spaced Spaced has been shown increase long-term retention of various types mathematics knowledge. Less clear whether spacing decreases performance during practice, with some studies indicating that it does and others not. To clarity, we tested produces gains, but short-term costs, calculus course. On worked on learning objectives either fashion (3 quiz) 3 quizzes). Spacing increased an end-of-semester test reduced quizzes. The reduction was nuanced: only first two questions, leaving third question unaffected. We interpret these findings evidence led more protracted, ultimately robust, learning. We, therefore, conclude imposes desirable form difficulty