Field tests of learning principles to support pedagogy: Overlap and variability jointly affect sound/letter acquisition in first graders.

Many details in reading curricula (e.g., the order of materials) have analogues in laboratory studies of learning (e.g., blocking/interleaving). Principles of learning from cognitive science could be used to structure these materials to optimize learning, but they are not commonly applied. Recent work bridges this gap by "field testing" such principles: Rather than testing whole curricula, these studies teach students a small set of sound-spelling-regularities over a week via an internet-delivered program. Training instantiates principles from cognitive science to test their application to vowel acquisition, a critical part of reading. The current study is a follow-up of Apfelbaum, Hazeltine, and McMurray (2013) and Roembke, Freedberg, Hazeltine, and McMurray (submitted), which found differing effects of consonant variability for learning vowels. In addition to investigating this discrepancy, this study examined a new principle: blocking/interleaving. While interleaved training is typically beneficial, this is difficult to apply in reading where there are many regularities. We compared a fully interleaved regime (six vowels) to two blocked regimes teaching two vowels on each block. Blocked conditions differed on whether vowels overlapped (EA with OA) or not (EA with OU). Blocking was crossed with consonant variability. 417 first graders were pre-tested on 6 vowels, and underwent 3-5 days of training, followed by a post-test and retention test. Blocking had little effect. However, there was a variability benefit when overlapping vowel strings were blocked together, and no effect of variability for interleaved training. Thus, benefits may only be observed if blocking highlights contrast between regularities. When applied to real-world skills, learning principles from cognitive science may interact in complex ways.