Developmental predictors of children's fraction concepts and procedures at the end of fourth
grade were investigated in a 2-year longitudinal study. Participants were 357 children who
started the study in third grade. Attentive behavior, language, nonverbal reasoning, number
line estimation, calculation fluency, and reading fluency each contributed uniquely to later
conceptual understanding of fractions. Number line estimation, attentive behavior,
calculation fluency, and working memory made unique contributions to acquisition of fraction …