A new survey of Valley teenagers reveals some disturbing trends about their drug use and sexual habits.

The report, from the Office on Children and Youth, is based on responses from eighth, tenth and 12th graders in Rockingham County and Harrisonburg.

It shows that, compared to a couple years ago, more of them are using marijuana, alcohol, and cigarettes, and more are having sex.

The study says half of the teens surveyed have used alcohol on the past year. A third have used tobacco, and 20 percent have used marijuana.

All of those numbers are higher than they were in 2007.

A former drug addict says overcoming early drug use can be very difficult.

"I started out smoking marijuana at the age of 15," says Kimberly Denman. "Marijuana's the gateway. Sooner or later you are not going to get high off marijuana anymore. You are going to need to get another high."

Denman chased that high for 20 years, going through acid, meth and cocaine.

"I kept taking them and taking them and taking them," says Denman. "I tried to get high, and I could not get high, so I ended up overdosing on them."

Denman dropped the drug habit three years ago, when her daughter was born.

Now she works at the Mercy House Thrift Store in Harrisonburg, setting the prices on hundreds of items. However, she is still calculating the cost of her drug abuse.

"You are cleaning your system out and now you're noticing the problems that you've done," says Denman.

The study is meant to inform parents and the community about youth behaviors, to help them decide the best way to keep teens from breaking the law or making bad decisions.

"We can use it as a tool," says Kim Kim Hartzler-Weakley, the Executive Director of the Office on Children and Youth. "To [say] 'OK, maybe we need a specific program addressing this.'"

Hartzler-Weakley says, despite the drug-use rates, the study shows that a majority of teens are doing what they are supposed to do.