These charts show the percent of King County and Washington State 6th, 8th, 10th, and 12th grade students who report that adults in their neighborhoods think youth alcohol, tobacco, and marijuana use is "very wrong". As you see, the older children get, the less likely they are to think adults disapprove of drug use.
Source:
2010 Healthy Youth Survey. King County results are posted on the Prevention WINS
website.