Research Findings: This study investigated the joint influence of maternal cognitive readiness to parent and children's self-esteem on children's academic achievement and behavioral adjustment in the classroom at age 10. Participants were 153 adolescent mothers and their firstborn children. Findings indicated that low levels of prenatal maternal cognitive readiness to parent were associated with impairments in children's achievement and adjustment at age 10, regardless of the children's level of self-esteem. Among dyads in which mothers were more cognitively prepared for the parenting role, however, children with higher self-esteem showed notably better achievement and adjustment compared to those with lower self-esteem. These results illustrate the joint influence of mothers' preparedness for parenting and children's self-esteem on the school performance of children who are generally considered to be at high risk for impairments in achievement and adjustment. Practice or Policy: Findings are discussed in terms of the enduring impact of cognitive readiness to parent and self-esteem on the academic achievement and behavioral adjustment of at-risk children, with a focus on implications for intervention and prevention based on the specific findings from this study. (Contains 5 tables and 1 figure.)