Objective. The purpose of this study was to test the effects of an education program in Tanzania designed to reduce children's risk of human immunodeficiency virus (HIV) infection and to improve their tolerance of and care for people with acquired immunodeficiency syndrome (AIDS.) Methods. A randomized controlled community-trial including baseline and 12-month follow- up surveys was employed. Public primary schools in the Arusha and Kilimanjaro regions of Tanzania were stratified according to location and randomly assigned to intervention (n = 6) or comparison (n = 12) conditions. Of the 1063 sixth-grade students (average age 13.6 years) who participated at baseline, 814 participated in the follow-up survey. Results. At follow-up, statistically significant effects favoring the intervention group were observed for exposure to AIDS information and communication. AIDS knowledge, attitudes toward people with AIDS, and the subjective norms and behavioral intentions toward having sexual intercourse. A consistent positive but nonsignificant trend was seen for attitudes toward having sexual intercourse and for initiation of sexual intercourse during the previous year (7% vs. 17%). Conclusions. It is feasible and effective to train local teachers and health workers to provide HIV/AIDS education to Tanzanian primary school children.