The purpose of this study is to conduct a randomized effectiveness trial to determine whether adding a preventive intervention at the transition from elementary to middle school is effective and cost effective in terms of ameliorating outcomes such as drug and tobacco use, participation in HIV- risking sexual behavior, delinquency, mental health problems, and school failure for young adolescents in foster care. The proposed LINKS intervention marries the goals of child welfare and educational systems. The aims are: a) to determine the effectiveness of the LINKS intervention on key behavioral health and school adjustment outcomes, b) to examine mechanisms of action; specifically the mediating effects of placement failure on outcomes, c) to examine the moderating role of fidelity on outcomes, and d) to examine cost effectiveness and cost avoidance of LINKS.