This study was conducted to assess the effectiveness of HIV/AIDS and the Life Skills Education delivery in primary schools in Tanzania. Specifically the study investigated pupils' views about the effect of HIV/AIDS and Life Skills teaching in primary schools in Tanzania; assessed pupils' knowledge related to HIV/AIDS and Life Skills education, and the effects of pupils' background characteristics on their knowledge about HIV/AIDS and Life Skills education. The study used mainly a questionnaire as the data collection instrument and involved 450 standard V, VI, and VII pupils from 10 schools in Morogoro Municipality. Findings showed that, though significant majority of pupils reported to have been taught about HIV/AIDS and related subjects, majority of them demonstrated a very low level of knowledge about HIV/AIDS. This raised some questions about the effectiveness of HIV/AIDS and Life Skills education in schools. On the basis of the findings of this study, it is recommended that there should be a review of the school curriculum with a view of strengthening the teaching of HIV/AIDS and Life Skills education.