Lifetime use of 11 chemical substances was assessed for subjects who were selected from youth enrolled in eight middle schools in urban, metropolitan, and suburban areas and who ranged in age from 10 to 16 years. Most students had some experience with alcohol (57.4 percent), 29.6 percent had smoked cigarettes, and 19.3 percent had used some illicit drug. Marijuana was the most commonly used illicit drug, followed by inhalants and amphetamines. Subjects were least likely to report the use of cocaine, narcotics, psychedelics, tranquilizers, and barbiturates. Limited levels of drug use were typically reported, and subjects reported conservative attitudes toward drug use. Variations between and among groups by gender, age, grade level, ethnicity, and community size are analyzed. 26 references, 3 tables, and 5 figures