How do toddlers learn the names of geometric forms? Previous work suggests that preschoolers have fragmentary knowledge and that defining properties are not understood until well into elementary school. The current study investigated when children first begin to understand shape names and how they apply those labels to unusual instances. We tested…

Various theorists have argued for the importance of a developmental approach to studying typical development (Karmiloff-Smith, 1998; Lerner, 1996; Lerner & Hood, 1986; Masten & Cicchetti, 2010; Overton, 2014; Overton & Lerner, 2012, 2014), and there are reasons to believe that this issue is even more critical to the study of…