(CNN) There is some good news when it comes to how many American children are doing drugs or drinking, but when it comes to marijuana the news is not as positive. That's according to the latest National Institute on Drug Abuse Monitoring the Future survey.
The survey annually talks with teens who are in eighth, 10th and 12th grade to get a sense of how many students are using illegal substances and exactly how much they are using.
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The news the NIH labels "encouraging" is the marked decrease in the number of teens who drink, smoke or use illegal drugs. The levels have fallen so much in so many of the categories that use of these drugs is at the lowest since the agency started doing the survey.
While use of illegal prescription drugs and heroin has increased among the adult population, teens don't seem to be as interested. The number of teens abusing prescription opioid pain relievers showed a significant decrease over the past five years, and among all the age-groups surveyed, heroin use was at the lowest rate since the agency started surveying teens. The same was true for several other substances, including synthetic cannabinoids, Vicodin, inhalants, methamphetamine, amphetamines, ecstasy and alcohol.
For eighth and 10th graders, Ritalin, Oxycontin, bath salts, hallucinogens and over-the-counter cough medicine use were at the lowest levels since these surveys started.
The agency asked only 12th graders about crystal meth and sedatives and use in that age-group was at its lowest rate since the survey began.
Overall, past-year use of illicit drugs for all grades combined was at 27.2%. That's down from a peak of 34.1% in 1997.
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Many high school seniors do seem to like to drink. Forty percent of 12th graders reported being drunk in the past year.
Teens also seem curious about e-cigarettes. While tobacco cigarette use was at its lowest rate in the survey's history, e-cigarettes were used by 9.5% of eighth graders, 14% of 10th graders and 16.2% of 12th graders in the past year.
Marijuana use did not decline among young people. The number of teens who used marijuana outpaced the number of kids who smoked tobacco. Some 6% of seniors in high school said they smoked marijuana daily. Among eighth graders, 6.5% said they smoked marijuana in the past month and 16.6% of 10th graders did. Among 12th graders, 21.2% said they tried marijuana in the last month. The perception of marijuana being a risky drug has shifted. Among 12th graders, 31.9% said they thought regular use could be harmful. Last year it was 36.1%.
Related: Frequent teen marijuana use linked to issues later in life
The general decline in drug and alcohol use by teens is part of a two-decade trend among American teens. However, Dr. Nora Volkow, the director of NIDA, cautioned that we should keep the positive statistics in perspective. "In spite of all of the movements in the right direction with all these areas, we still have very high rates overall in our country," Volkow said. That's when compared to other countries, according to global surveys. "We still have lots of work to do."