| 3 | Impacts of a Violence Prevention Program for Middle Schools: Findings After 3 Years of Implementation | Impacts of a Violence Prevention Program for Middle Schools: Findings After 3 Years of Implementation | Suyapa Silvia; Jonathan Blitstein; Jason Williams;Chris Ringwalt;Linda Dusenbury;William Hansen | U.S. Department of Education;Institute of Education Sciences;National Center for Education Evaluation and Regional Assistance | 2011/05 | | |