07/01/2010 11:45 am ET | Updated Nov 17, 2011

Underage Drinking Soars Among Teen Girls (VIDEO)

The Fourth of July is prime time for teen drinking, and this year might be worse than usual. Alcohol and drug abuse in young people has taken a shift from a decades-long decline to a sharp increase in the last two years, according to a new study by the Drug Abuse Warning Network.

From 2008 to 2009 alcohol abuse went up 11 percent, and marijuana use up 19 percent, the study shows. And here's another interesting find: more girls than ever are drinking and doing drugs.

"Young women in some of these studies have been shown to be equaling their male counterparts," child and adolescent psychologist Dr. Jennifer Hartstein told CBS. "Which was not usually the case. So we have to question why."

What can parents do about it? Be sure not to lie about your own personal alcohol consumption, warns Hartstein. Educate your kids about the pros and cons of drinking, and the consequences of their choices. "The earlier you get involved as a parent and educate your kids, the more protective that is."