If you're paying attention, you know I'm generally pro-legalization.
So, I have a plan that will allow for legalization and decrease use among the young (ignoring the evidence that simple legalization or decriminalization will do that anyway):
1. Legalize, or at least medicalize and decriminalize, most illegal drugs. This will have the immediate effect of taking them away from the province of gangsta and underground culture, which, unsavory as the reality may be, has been romanticized beyond all reason.
2. After fast-tracked medical testing (after all, long-term data on safety isn't that hard to get once users don't have fear or prosecution), prescribe liberally for ailments mainly associated with the elderly wherever and whenever appropriate.
Voila, you have just made most street drugs as cool as grandpa's heart medication.