Limitations of the retrieval strategy dimension of Siegler's (1982, 1984) distributions-of-associations model of young children's estimation of sums are delineated, an alternative model is described, and findings of two studies designed to test key assumptions of the models are reported. In Study 1, kindergarten children with normal IQ and no…

Students in grades 1, 3, 4, 5, 6, and college were timed as they produced the answers to simple addition problems or verified a given problem as true or false. First graders clearly relied on a counting process for their performance, as advanced by the Groen and Parkman "min" (for minimum addend) model. Third grade appears to be a…