A study by researchers at the University of Michigan finds that alcohol use among American teens is at a historic low, but the number of young people choosing to use drugs is at a 30-year high.
The number of young people using any illicit drugs, especially marijuana, has risen gradually over the past four years.
In 2011, 50 percent of high school seniors reported having tried an illicit drug at some time, 40 percent had used one or more drugs in the past 12 months, and 25 percent had used one or more drugs in the prior 30 days.
The figures are lower for younger teens, though still high: among 10th graders, 38 percent reported having tried an illicit drug, 31 percent used in the past 12 months, and 19 percent in the prior 30 days.
The report indicates that the number of high school students who say they used marijuana 20 or more times over the course of a month is also on the rise.
The report says that while marijuana use is on the rise, from 1991 to 2011 alcohol use among teens dropped sharply. The number of 8th graders reporting any use of alcohol in the prior 30 days has fallen by about half to 13 percent, among 10th graders by more than one-third to 27 percent and among 12th graders by about one-fourth to 40 percent.