Legalizing medical marijuana might be good for grannies with glaucoma, but there's been, at the least, a correlation between the rise of legit weed and teen toking.

The latest Monitoring the Future survey of teen drug use in America finds that “daily marijuana use is now at a 30-year peak level among high school seniors.”

Whew. That's Fast Times at Ridgemont High levels, given that the all-time peak of pot use was said to be in 1979, around the time Cameron Crowe was hanging out at a San Diego high school to research the basis of the film.

According to the annual survey, conducted by the University of Michigan, pot use among high schoolers was up for the fourth straight year.

More than one in 10 teens had tried synthetic marijuana last year.

Strangely, according to a Monitoring the Future statement (PDF), drinking ” … continued a long-term gradual decline among teens, reaching historically low levels in 2011.”

According to survey data teen pot use hit a low around 1992 and dipped again around 2006 but has seen a gradual rise in recent years, the same period that medical marijuana has been legalized in about 16 states nationwide.

More than one-third of 12th graders (36.4 percent) (PDF) said they toked up in the last year.

Lloyd Johnston, principal investigator:

… One in every fifteen high school seniors today is smoking pot on a daily or near daily basis. And that's the highest rate that we have seen over the past thirty years–since 1981.

We're just waiting for the return of the hair metal.

[@dennisjromero / / @LAWeeklyNews]

LA Weekly