Dyscalculia, or mathematics learning disorders, is currently known to be heterogeneous (Wilson & Dehaene, 2007). While various profiles of dyscalculia coexist, a general and persistent hallmark of this math learning disability is the difficulty in memorizing arithmetic facts (Geary, Hoard & Hamson, 1999; Jordan & Montani, 1997; Slade…

Many models of learning rely on accessing internal knowledge states. Yet, although infants and young children are recognized to be proficient learners, the ability to act on metacognitive information is not thought to develop until early school years. In the experiments reported here, 3.5-year-olds demonstrated memory-monitoring skills by…