Basic and applied research related to the effects of interspersing trials of maintenance (i.e., review) tasks among trials of acquisition tasks on academic skill development is reviewed. In general, empirical research suggests that interspersing procedures are effective in facilitating acquisition, learning rate, and maintenance. However, some inconsistency exists among the data that suggests student learning, in some instances, may be impeded. Research also suggests that interspersing procedures are not conducive to facilitating generalization. The discrepancy between various research findings and the consistent failure of research on interspersing procedures to increase generalization is critically reviewed in relation to a hierarchical learning theory set forth by Haring and Eaton (1978). From this hierarchical learning theory perspective, inconsistent results may be better understood and predicted. Implications for current practice and directions for future research are also discussed.