The annual study of college student drug use by University of Michigan's Institute for Social Research has found that student use of marijuana continues to be up, but that other drug use is falling.
In 2015, 38 percent of college students said they had used marijuana in the prior 12 months, up from 30 percent in 2006. Daily or near-daily use was at 4.6 percent, down from 5.9 percent in 2014, but up from 3.5 percent in 2007.
Most other drug use is down, however. For example, the percentage of students reporting heroin use in recent years has regularly been below 0.3 percent, and it was down to 0.1 percent in 2015.