When learning new information, should students focus on studying 1 concept at a time or should they alternate studying between different concepts? Recent research shows that students should mix up or interleave the study of different concepts, particularly when the concepts are related or hard to discriminate (Carvalho & Goldstone, 2015). But students rarely study only 1 course, so how should the study of unrelated courses be sequenced? Should the study sessions be blocked by course to avoid unproductive juxtapositions or be interleaved across different courses because it inherently involves spaced practice, which is also effective for learning? In Experiments 1 and 2, we explored how students construct their study sessions by using hypothetical scenarios. Finally, in Experiment 3, we experimentally manipulated the study sequence of related concepts within 2 unrelated domains (i.e., physics and statistics). Given only 1 level to schedule (related modules or unrelated courses; Experiment 1), students chose to block related modules but to interleave unrelated topics--even though the literature suggests the related concepts are more likely to benefit from interleaving. Given 2 levels to schedule (concepts and domains; Experiment 2), students chose to interleave everything--even though empirical data from Experiment 3 suggests that the optimal schedule involves interleaving at either the concept or the domain level, but not both or neither.