A public-school-based epidemiological survey of fourth-grade students in Washington, DC, was performed in 1988/89 (n = 4675) and 1990/91 (n = 4678). Comparisons of data for the two periods revealed that the lifetime prevalence of self-reported alcohol use, alcohol use without parental knowledge, and smoking more than a puff of cigarettes declined; marijuana use and cigarette experimentation did not. Seven variables were associated with use. Declines were observed in perceived peer pressure to use; seeing a family member/friend selling drugs; and being offered alcohol, cigarettes, or marijuana by peers. No declines were observed in family use, perceived friends' use, being bothered a lot if best friends use, or seeing someone else selling drugs.