The attached You tube video says it all in terms of why "punishment" based approaches do not work. While focussing on crimes and adults this equally applies to youth and children where adults and systems punish, isolate and shame individuals as a result of the choices they have made.
Joshua- Crime and Punishment
http://www.youtube.com/watch?v=yMCJn6R2xXM
Joshua- Crime and Punishment
http://www.youtube.com/watch?v=yMCJn6R2xXM