Multivariate sets of predictor variables including both cognitive and social variables, different types of preschool experiences, and family environment variables were used to predict the first-grade reading achievement of 144 first-grade boys and girls. Measures for the predictor variables had been taken at school entry and at the end of the kindergarten year. Using multiple regression and commonality analysis, results on the Standard Reading Test Number 1 (Daniels and Diack, 1970) indicated that, although complex multiple interactions among variables were related to reading achievement, the strongest predictors of reading ability were sex and social class. Thus, support was given to the traditionally held notion that it is children from the middle class, and girls in particular, who are the better readers. (Author/MP)