This is the second report on the school achievement of children 6-11 years old in the noninstitutionalized population of the United States as estimated from the Reading and Arithmetic subtest data of the Wide Range Achievement Test (WRAT) obtained in the Health Examination Survey of 1963-65. It contains findings by selected demographic and socioeconomic variables. Three different survey programs are utilized in the National Health Survey. The report contains findings from the Reading and Arithmetic subtests of the WRAT by age, sex, race, region, size of place of residence and population change from 1950 to 1960, family income, education of parent, and grade in school. These findings are shown in terms of raw scores, standard scores, and grade equivalents. A battery of tests, designed to assess some aspects of mental growth and behavioral development, was included as part of the standardized examination. Significant differentials in school achievement were found over all variables which were considered. (Author/WS)