In 1995, Mark Cohen, Vanderbilt University Law Professor, calculated that the monetary value of "saving" one high-risk youth was between $1.7 million and $2.3 million, based on costs to crime victims and the criminal justice system, the costs to society of heavy drug abuse and the economic impact of dropping out of high school.

Using new data, Professor Cohen and City University of New York criminal justice professor Alex Piquero  have updated this information.  The report can be downloaded as a PDF from the link above.