Beginning in 1991, we enrolled 6350 healthy infants less than 62 days of age and evaluated them at least monthly until they reached three years of age. We randomly assigned 429 of the children who developed persistent middle-ear effusion before reaching that age to have tympanostomy tubes inserted either promptly or up to nine months later if effusion persisted. At three, four, and six years of age we systematically assessed the children’s cognitive, language, speech, and psychosocial development. In the present study, using a standardized battery of assessments, we evaluated literacy, attentional abilities, social skills, and academic achievement in 391 of these children at nine to eleven years of age.