The marijuana naysayers were wrong yet again. They tried to terrify parents into thinking that legalizing pot in Colorado would lead to a drastic increase in bleary-eyed, stoned teenagers, but that hasn’t been the case. In fact, new federal survey data shows that fewer kids have used marijuana since it was legalized in the state in 2014. 
The data comes from the National Survey on Drug Use and Health. It shows that 18.35% of Coloradans ages 12-17 had used weed in the past year in 2014 or 2015, a sharp decrease from 20.81% in 2013/2014. (In this survey, years are paired for state-level data to provide larger sample sizes). That’s a drop of approximately 12%.
That’s a really good thing, not just because it proves the critics wrong, but because adolescents who use marijuana may be more likely to abuse marijuana or develop mental health problems because of it, because their brains are still developing. I think we can all agree that with marijuana legalization should also come reasonable restrictions, and lots of quality education.
As a matter of fact, pot use fell in all states during that time period, including in Washington, where marijuana was also legalized in 2014. However, that drop wasn’t statistically significant.
Read: Debunking the Myth: Legal Weed Does not Increase Teen Marijuana Consumption
Among adults, however, marijuana use rose significantly in the state over the same time period. Among Coloradans age 26 and older, past-year marijuana use increased from 16.80% in 2013/2014 to 19.91% in 2014/2015. Marijuana use among adults generally rose in all states during that time. In Colorado and Washington, you must be over 21 to legally purchase weed.
There is no clear reason why marijuana use among teens has dropped, but there are a few theories. One theory is that the black market simply isn’t as big as it was before legalization, so it might actually be harder for kids to get their hands on pot. Or it could be that better substance abuse prevention programs are working. It’s likely a combination of things.
In the interest of transparency, it’s important to point out that the federal survey data shows marijuana use among teens remains higher in Colorado than in any other state. Quite a bit higher, really. However, other sources indicate that teen marijuana use in Colorado is smack dab in the middle when it comes to use nationwide.
Colorado’s own survey data indicates that fewer teens are using pot post-legalization. The Colorado Department of Public Health and Environment released its biannual “Healthy Kids Colorado Survey” in June, which showed that 4 out of 5 high school students continue to say they don’t use marijuana, not even once in a while. 
That survey also found that about 21% of high school students in Colorado said they’d used marijuana within the past 30 days in 2015 – a slight decline from 22% in 2011.
The 21% 30-day use in Colorado represents a decline of about 4 points since 2009, when medical marijuana stores began popping up around the state.
Whatever the reasons behind the decrease in teen pot use may be, marijuana opponents’ fears that more kids would start using pot after legalization have been unfounded.
Mason Tvert, spokesman for the pro-legalization Marijuana Policy Project, said:
“Decades of arresting and prosecuting countless adults failed to prevent teens from accessing and using marijuana. States like Colorado and Washington are taking a new approach and actually controlling the production and sale of marijuana.” 
“Survey after survey is finding little change in rates of teen marijuana use despite big changes in marijuana laws around the nation. Colorado and Washington are dispelling the myth that regulating marijuana for adult use will somehow cause an increase in use among adolescents.”