Learning to measure through action and gesture: Children's prior knowledge matters.

Learning through physical action with mathematical manipulatives is an effective way to help children acquire new ideas and concepts. Gesture is a type of physical action, but it differs from other kinds of actions in that it does not involve interacting directly with external objects. As such, gesture provides an interesting comparison to action-on-objects and allows us to identify the circumstances under which gesture versus interaction with objects (and the associated effects on the external world) may be differentially beneficial to learning. In the current study, we ask whether individual differences in first grade children's prior knowledge about a foundational mathematical concept - their understanding of linear units of measure - might interact with their ability to glean insight from action- and gesture-based instruction. We find that the children using a more rudimentary pretest strategy did not benefit from producing gestures at all, but did benefit from producing actions. In contrast, children using a more conceptually advanced, though still incorrect, strategy at pretest learned from both actions and gestures. This interaction between conceptual knowledge and movement type (action or gesture) emphasizes the importance of considering individual differences in children's prior knowledge when assessing the efficacy of movement-based instruction.