But the researchers and public officials who crunch those numbers warned that some of the statistics gleaned from an annual survey of 46,000 American eighth-, 10th- and 12th-graders were worrisome.
Take marijuana use, which had declined steadily among teens since the mid-1990s. This year, 19.4% of high school seniors said they had smoked marijuana at some point in the prior 30 days, as did 13.8% of 10th-graders and 5.8% of eighth-graders. The downward trend has stalled in the last two years, and kids' attitudes suggest a reversal may be ahead.
In 1991, 58% of eighth-graders said they thought occasional marijuana use was harmful. By last year, that number had fallen to 48%, and this year, to 45%.
In a Washington, D.C., news conference Monday, Gil Kerlikowske, the Obama administration's drug czar, called such numbers "a warning sign."
"When beliefs soften, drug use worsens," said Kerlikowske, whose office is expected to release its first policy initiatives to combat and treat drug abuse in February.
University of Michigan researcher Lloyd Johnston, who oversees the annual survey, said there was "serious softening" in the perceived risks of LSD, inhalants and the party drug Ecstasy -- a sign that "a new generation of kids are interested . . . in rediscovering these drugs, because they don't understand why they shouldn't be using them."
Johnston also flagged a phenomenon the survey has recently begun to track -- "extreme binge drinking," or the consumption of more than 10 drinks on a single occasion. Coming on the heels of the weekend death of South Pasadena's Aydin Salek, an 18-year-old suspected of having succumbed to alcohol poisoning, the survey's findings suggest that such high-risk drinking is not unusual among older teens.
Binge drinking, defined as consumption of five drinks or more in a row, has declined since peaking in 1983. But Johnston said there has been "not much decline" in numbers of extreme binge drinkers.
Among high school seniors, 11% said they had drunk 10 drinks or more in a row in the two weeks prior to the survey; 6% said they'd had 15 or more.
The survey also showed that U.S. adolescents continue to raid their parents' and friends' medicine chests. Use of prescription painkillers is at an all-time high: 10% of high-school seniors reported taking Vicodin for nonmedical reasons in the last year, and 5% reported taking OxyContin.
Dr. Nora Volkow, director of the National Institute on Drug Abuse, which has commissioned the survey for 35 years, said at the news conference that teen use of prescription stimulant drugs is holding steady, with just over 7% of 10th- and 12th-graders reporting they had taken amphetamines -- drugs prescribed to many kids in treatment of attention-deficit hyperactivity disorder -- for nonmedical reasons. Volkow said that in many cases, teens take these drugs before tests or study sessions as "cognitive enhancers."
Although fewer kids reported taking Ritalin, much of that decline was because kids had merely shifted to Adderall, a newer ADHD drug.
The officials said that youths report some confidence that prescription drugs are less harmful than street drugs.
In the survey's first accounting of where kids get drugs, it found that 66% who reported illicit drug use said they got the drugs from a friend or relative. Almost 19% said they got drugs with a doctor's prescription.