Is Illegal Marijuana Gaining Popularity in the Life of the Teenager?

According to an article written by Remy Melina, Research conducted by scientist Dr.Esther Choo shows that surveys conducted in high schools and middle schools from 1997 to 2009, have had a similiar result in the usage of marijuana for teenagers. Who would've knew?
http://www.myhealthnewsdaily.com/legalizing-medical-marijuana-teen-drug-use-2073/