The analyses presented are based on a sample of 80 girls and 67 boys who were followed from first grade to age 14. The study began in the spring of 1978 as part of the Concordia University High Risk Project. Disruptive behavior was assessed in grade 1; school achievement was assessed in grades 1 and 4; and delinquent behavior and antisocial personality were assessed at age 14. Findings from the self-reported delinquent behavior at age 14 indicate that the best model for boys' delinquent behavior was a direct causal link between grade 1 disruptive behavior and delinquent behavior. Poor school achievement was not a necessary causal factor. For the girls, all three models failed to produce a good fit for the delinquent behavior data. As for delinquent personality (extraverted, neurotic, and tough-minded, with an antisocial value system), results indicate that, for both boys and girls, poor school achievement was a necessary component of the causal path between grade 1 disruptive behavior and age 14 delinquent personality. 4 figures, 2 tables, and 41 references (Author abstract modified)