The effects of prior encodings of manipulatives (red and blue plastic chips) on children's ability to use them as representations of quantity were tested. First graders (N = 73) were assigned to four conditions in which the encoding of plastic chips was experimentally manipulated. All children then participated in an addition activity that relied…

Two studies examined children's map construction skills when drawing demands were removed from the task and scenes were highly simplified. Study 1 compared the performance of first graders and third graders on their ability to preserve configuration during transformation of pictured arrays from eye-level to aerial views. For children with…