A typical mathematics assignment consists of one or two dozen practice problems relating to the same skill or concept, yet empirical evidence suggests that there is little or no long-term benefit from working more than a few problems of the same kind in immediate succession. Alternatively, randomized experiments in the laboratory and classroom have shown that scores on delayed tests improve markedly when most of the practice problems are arranged so that (a) problems of the same kind are distributed across many assignments spaced weeks apart, and (b) problems of different kinds are interleaved within the same assignment. In this commentary, we describe these math practice strategies and suggest additional lines of research regarding students’ and teachers’ perceptions of the efficacy and difficulty of these strategies.

一个典型的数学作业由一到两个与同一技能或概念相关的练习题组成，但经验证据表明，连续多次从事多个同类问题几乎没有或没有长期利益。另外，实验室和教室中的随机实验表明，如果安排了大多数练习问题，则延迟考试的分数会明显提高，因此（a）相同类型的问题分布在许多作业中，间隔数周，并且（b）问题同一作业中交错插入不同类型的数据。在这篇评论中，我们描述了这些数学练习策略，并就学生和教师对这些策略的功效和难度的看法提出了其他研究思路。