Trained teachers are more likely to implement, and to implement more of the curriculum than untrained teachers, according to the Blueprints for Violence Prevention Initiative, which identifies effective violence prevention and drug prevention programs that have been evaluated in rigorous, controlled trials. In addition, fully trained teachers complete a greater percentage of the program with greater fidelity, They also are more effective and have more favorable student outcomes than untrained teachers. Teachers without follow and support over time often fail to fully implement or continue use of a program.

Source: Mihalic S, Irwin, K, Fagan, A, Ballard, D. and Elliott, D. (July 2004 "Successful Program Implementation: Lessons from Blueprints." Juvenile Justice Bulletin. Office of Justice Programs, Washington, D.C.