Despite the importance of learning abilities and disabilities in education and child development, little is known about their genetic and environmental origins in the early school years. This study reports results for English (which includes reading, writing, and speaking), mathematics, and science as well as general cognitive ability in a large and representative sample of U.K. twins studied at 7, 9, and 10 years of age Presents new univariate, multivariate, and longitudinal analyses that systematically examine genetic and environmental influences for the entire sample at all ages for all measures for both the low extremes (disabilities) and the entire sample (abilities) Draws conclusions have far-reaching implications for education and child development as well as for molecular genetics and neuroscience