Contents: Preface. Part I: Studies of Microgenesis of Cognitive Change: Behavioral Approaches.S. Goldin-Meadow, Giving the Mind a Hand: The Role of Gesture in Cognitive Change. R.S. Siegler, Children's Discoveries and Brain-Damaged Patients' Rediscoveries. Neuroscience Approaches.M.M. Merzenich, Cortical Plasticity Contributing to Child Development. J.L. McClelland, Failures to Learn and Their Remediation: A Hebbian Account. R.J. Haier, PET Studies of Learning and Individual Differences. Commentary.J.W. Stigler, Breakthroughs in Using Individual Differences to Study Learning: Comments on Goldin-Meadow, Haier, McClelland, Merzenich, and Siegler. Part II: Studies of Change Over Longer Time Scales: Behavioral Approaches.E. Thelen, Dynamic Mechanisms of Change in Early Perceptual-Motor Development. R. Case, M.P. Mueller, Differentiation, Integration, and Covariance Mapping as Fundamental Processes in Cognitive and Neurological Growth. D. Kuhn, Why Development Does (and Does Not) Occur: Evidence From the Domain of Inductive Reasoning. Neuroscience Approaches.M.H. Johnson, M. de Haan, Developing Cortical Specialization for Visual-Cognitive Function: The Case of Face Recognition. H.J. Neville, D. Bavelier, Variability of Developmental Plasticity. Commentary.D. Klahr, Time Matters in Cognitive Development. Part III: Developmental Disorders: Dyslexia.A.M. Galaburda, G.D. Rosen, Neural Plasticity in Dyslexia: A Window to Mechanisms of Learning Disabilities. Attention Deficit Disorder.B.J. Casey, Disruption of Inhibitory Control in Developmental Disorders: A Mechanistic Model of Implicated Frontostriatal Circuitry. Autism.P.A. Carpenter, M.A. Just, T. Keller, V. Cherkassky, J.K. Roth, N. Minshew, Dynamic Cortical Systems Subserving Cognition: fMRI Studies With Typical and Atypical Individuals. Concluding Commentary.M.I. Posner, Education on the Human Brain: A Commentary.