Washington ? Teenagers say marijuana is easier to buy than cigarettes or beer one in three say they can find it in a matter of hours but only 25 percent admit trying it, a national survey finds.

When the National Center on Addiction and Substance Abuse polled 1,000 teens last winter, 27 percent said they could buy marijuana in an hour or less; another 8 percent said it would take a few hours. But for the first time since the study began in 1996, teenagers said it was easier to buy marijuana than cigarettes or beer.

The annual survey didn’t specify whether drugs are easy or difficult to buy at school, but 63 percent of students said their schools are “drug-free,” nearly double the number who said the same in 1998. It’s the highest percentage since 1996.

While many have criticized nationally used anti-drug programs such as D.A.R.E., educators said years of using such programs seem to be paying off.

“I think we’re starting to see the fruition of some of those programs,” said Gerald Tirozzi, executive director of the National Association of Secondary School Principals.

He said student drug use has been dropping for the past four or five years as communities began financing anti-drug programs. “There has been a sense that the drug problem, while not solved, has been improving,” he said.

More than half of students said they didn’t drink alcohol in a typical week, and about as many said they have never had a drink.

While one in four pupils said at least one parent smoked cigarettes, 69 percent said they had never smoked.

Joel Willen, principal of Pershing Middle School in Houston, said teachers and administrators were seeing less drug activity at school. “I think the kids are not bringing whatever it is they’re doing, if they’re doing it, to school,” he said.

Pershing’s drug-prevention programs are paired with a get-tough policy on drugs that includes twice-yearly, random locker and backpack searches by drug-sniffing dogs, Willen said. Students caught using or selling drugs can be sent to an alternative school or even expelled.

“They know we take a real hard line on drugs,” he said.

The survey also found that:

8 percent of students believe there’s a teacher at their school who uses illegal drugs.

25 percent said they had seen illegal drugs being sold at school.

55 percent said they’d report someone they saw using drugs at school.

56 percent said they’d report someone they saw selling drugs at school, the highest level since 1996.

24 percent said drugs were “the most important problem facing people your age,” highest among several problems such as crime, peer pressure, sexuality and the environment.

The National Center on Addiction and Substance Abuse, based at Columbia University, polls teenagers on drug use and the presence of drugs in schools. This year’s random telephone survey of students age 12-17 was conducted Dec. 27, 2001-Feb. 6, 2002, by QEV Analytics. It has a margin of error of plus or minus 3.1 percent age points.

An accompanying survey of parents found them equally divided on their children’s drug habits: 44 percent said it was “not very likely” their child would ever try illegal drugs, but 43 percent said it was “very likely” or “somewhat likely” that their kids will try them.

The federal Centers for Disease Control and Prevention estimates that, by the time they complete high school, 47 percent of teenagers have smoked marijuana, 24 percent have used another illicit drug, and 81 percent have drunk alcohol. The agency also estimates that 70 percent have smoked cigarettes.