Among students surveyed as part of the 2005 Monitoring the Future study, 16.5% of eighth graders, 34.1% of tenth graders, and 44.8% of twelfth graders reported lifetime use of marijuana. In 2004, these percentages were 16.3%, 35.1%, and 45.7%, respectively.

Approximately 74% of eighth graders, 65.5% of tenth graders, and 58% of twelfth graders surveyed in 2005 reported that smoking marijuana regularly was a “great risk.”

The Youth Risk Behavior Surveillance (YRBS) study by the Centers for Disease Control and Prevention (CDC) surveys high school students on several risk factors including drug and alcohol use. Results of the 2005 survey indicate that 38.4% of high school students reported using marijuana at some point in their lifetimes. Additional YRBS results indicate that 20.2% of students surveyed in 2005 reported current (past month) use of marijuana.

Between 2001 and 2005, marijuana use dropped in all three categories: lifetime (13%), past year (15%) and 30-day use (19%). Current marijuana use decreased 28% among 8th graders (from 9.2% to 6.6%), and 23% among 10th graders (from 19.8% to 15.2%).