The study found that chronic maltreatment, poorer daily living skills, and lower intelligence explained a substantial proportion of the variance in maltreated children's math scores (39 percent); whereas, type of maltreatment, poorer daily living skills, and lower intelligence explained a substantial proportion of the variance in reading scores (54 percent) over time. Contrary to the authors' hypothesis, having a behavioral problem apparently protected chronically maltreated children from poorer performance in math over time. The authors advise that in order to increase academic achievement among maltreated children, it is important to prevent chronic maltreatment and assist children in increasing their competency in daily living skills. Data from the National Survey on Child and Adolescent Well-Being (NSCAW) - the first national probability sample of children and their caregivers investigated by child protection services (CPS) systems in the United States - were used to test the hypotheses. The 6,228 children in the sample were selected between October and December 2000, using a two-stage stratified sampling design. The children were selected from 92 primary sample units from 97 counties nationwide. Children's academic achievement was examined at three time periods: baseline, 18 months from baseline, and 3 years from baseline. The final sample consisted of 702 children (378 girls and 324 boys). Each child completed the reading and math tests, and data were collected from child assessments/interviews, caregiver interviews, and CPS investigators. 5 tables, 1 figure, and 61 references