Nearly one in 10 teenagers are smoking marijuana at least 20 or more times a month, a new survey finds. The Associated Press reports that the survey, released Wednesday by The Partnership at Drugfree.org, found past-month use of marijuana rose from 19 percent in 2008, to 27 percent last year.

The Partnership Attitude Tracking Study found past-year use of marijuana rose from 31 percent in 2008, to 39 percent (six million teens) in 2011. The survey found lifetime use increased from 39 percent in 2008, to 47 percent (eight million teens) in 2011. The last time marijuana use was this widespread among teens was in 1998, when past month use of marijuana was at 27 percent.

"Parents are talking about cocaine and heroin, things that scare them," Steve Pasierb, President and CEO of The Partnership at Drugfree.org, told the AP. "Parents are not talking about prescription drugs and marijuana. They can't wink and nod. They need to be stressing the message that this behavior is unhealthy."

The survey suggests an association between teens who smoke marijuana more regularly and the use of other drugs. Adolescents who smoked 20 times or more a month were almost twice as likely, as those who smoked marijuana less often, to use Ecstasy, cocaine or crack.

The survey suggests teen marijuana use has become a normalized behavior. Only 26 percent agree with the statement, "In my school, most teens don't smoke marijuana," down from 37 percent in 2008. Also, 71 percent of teens say they have friends who use marijuana regularly, up from 64 percent in 2008.

According to the survey, 10 percent of teens said they used prescription pain medication in the past year, down from a peak of 15 percent in 2009, and 14 percent in 2010.

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