The use of other drugs such as marijuana on school property may also cause disruptions in the learning environment. The consumption of these substances leads to a school environment that is harmful to students, teachers, and school administrators.

• Between 1993 and 1997, 6 to 9 percent of students in grades 9 through 12 reported using marijuana on school property during the last 30 days. About 18 to 26 percent reported using marijuana anywhere during the last 30 days (figure 19.1 and table 19.1).
• There was an increase in the use of marijuana among students between 1993 and 1995. In 1995, about 25 percent of all students in grades 9 through 12 had used marijuana in the last 30 days, compared with 18 percent in 1993 (figure 19.1 and table 19.1). Marijuana use in 1997, at 26 percent, was similar to that in 1995. However, marijuana use on school property did not increase significantly between 1993 and 1995, or between 1995 and 1997.
• Males were more likely than females to have used marijuana in every survey year (figure 19.1 and table 19.1), both in general and on school property.
• Both males and females increased their overall use of marijuana from 1993 to 1997 (figure 19.1 and table 19.1). The percentage of males who reported using marijuana in the 30 days before the survey increased from 21 percent in 1993 to 30 percent in 1997. The percentage of females increased from 15 percent to 21 percent.
• Students' grade in school was not associated with their use of marijuana on school property (figure 19.2 and table 19.1). However, in 1993 and 1995, students in lower grades were less likely than students in higher grades to report using marijuana at any time during the last 30 days. In 1997, this difference by grade was not apparent, with students in lower grades about as likely to report using marijuana as students in higher grades. This pattern occurred because the overall use of marijuana in 9th, 10th, and 11th grades increased from 1993 to 1997, while its use by 12th graders remained relatively constant.