The purpose of this study was to determine the effects of alcohol use on student behaviors in Ontario schools. The study was designed to investigate the prevalence of alcohol use by students in grades 7-13 and the effects of drinking on classroom and school behaviors by interviewing both students and teachers. The teachers were surveyed to determine their awareness and perceptions of drinking problems at their school. The report presents a short review of the pertinent literature, a description of the research methods, and the findings from both the student and teacher questionnaires. The major findings provide an indication of the extent to which alcohol use causes problems in schools throughout the Province, the types of problems drinking creates, the extent and frequency with which students use beer, wine, liquor, and other drugs, the relationship between drinking and the use of other drugs, the effects of drinking on social relationships, and the extent to which grade, grade average, and sex influence alcohol-related student behaviors. (Author)