One obstacle to understanding abstract concepts such as the "control of variables" strategy (CVS) is the tendency for learners to focus on surface rather than deep features in instructional materials. However, in tasks such as learning CVS, these same surface features may also support understanding, provided learners realize the…

Hands-on science typically uses physical materials to give students first-hand experience in scientific methodologies, but the recent availability of virtual laboratories raises an important question about whether what students' hands are on matters to their learning. The overall findings of two articles that employed simple comparisons of…