This report is a description of self-reported health behavior and attitudes of American youths based on questionnaire responses of a national probability sample of noninstitutionalized youths, 12 through 17 years of age. Topics include behavior and attitudes relating to general health status, cigarette smoking, physical appearance, personal independence, use of leisure time, values, perception of the need for medical or dental care, and aspects of social behavior. Variations in health behavior and attitudes associated with the age attitudes associated with the age and sex of the youths are also discussed. Fifty detailed tables are included. Appended are technical notes and self-report questionnaire forms. (Author/RC)