The study found that school performance at 14 years old predicted the frequency of cannabis use in young adulthood. Children who had lower school performance at age 14 were more likely to report the frequent use of cannabis at 21 years old, with the association being stronger for frequent cannabis users. This link between school performance at age 14 and subsequent cannabis use was independent of possible family and individual factors, including the child’s IQ. One explanation of these findings is that both drug use and poor school performance stem from a personal rejection of conventional social values; however, study findings suggest the association between school performance and cannabis use is independent of several indicators of deviant behavior, including acting-out behavior at 5 years old or 14 years old, smoking, and alcohol consumptions at 14 years old. A second possible pathway is that cannabis use is a consequence of poor academic achievement that leads to frustration and distress that stimulates coping through cannabis use. A third possibility is that poor school performance separates the individual from achieving peers and increases the attraction to deviant peers who also are coping with peer school performance. These analyses were based on data from 3,478 young adults who completed the 21-year questionnaire for the children of women participating in the Mater University of Queensland longitudinal study of women who gave birth to children at the Mater Misericordiae Hospital in Brisbane, Australia, between 1981 and 1983. 3 tables and 39 references