Marni, I'm afraid the literature is not too encouraging on the likelihood of making inroads with juveniles in prison. By about 5th grade, most conduct-disordered or undersocialized kids are said to pretty much be cooked. Having said that, I am thinking now of a program I saw where they placed adjudicated kids in special ed classes for the severly disabled and used them as aides. It make a big impact on some of the kids, though I don't know if anyone ever published something on the program.
You might look at Arnold Goldstein's programs for aggression replacement and social skills. Consider as well that many incarcerated kids (and adults!) have learning problems, can't read, etc.