Broadcast date: 9/14/2017 Many experts believe the increased legalization of marijuana in the U.S. has contributed to the growing belief that marijuana is harmless among youth. With this misperception, youth are using the drug at increased rates. For example, t he 2016 VITAL SIGNS reports shows a major increase in marijuana consumption among San Luis Obispo County teens. It reported forty-one percent of eleventh graders used marijuana in the past 30 days, compared to just 26% in 2013. A 15%