Full text can be accessed at http://www.tandfonline.com/doi/abs/10.1080/17450120802183710This study has investigated human immunodeficiency virus (HIV) knowledge, attitudes and sexual at-risk behaviours of youths from disadvantaged communities of Dar es Salaam, Tanzania. Participants were 800 youths aged 12–15 years within three youth subgroups in these poorer communities: those children attending school; children who were not attending school but who were still residing within their communities; and children who were street children (more than 50% of them being orphans). Participants responded to questionnaires. In general, all youths showed low levels of HIV knowledge, experience with condom use and intention to use condoms. They exhibited moderate perceived behaviour control in using condom and positive subjective norms about the use of condoms, the value of sexual abstinence and having an exclusive sexual partner. Contrary to expectations, there were no significant differences between those in-school and those out-of-school with regard to HIV knowledge, intended condom use, subjective norms about condom use and abstinence. Indeed, the in-school children were more at risk for HIV infection, in that they reported the lowest condom experience and perceived behavioural control in condom use. There were systematic gender differences, in that girls scored lower than boys on all variables. The policy of basing HIV/acquired immunodeficiency syndrome (AIDS) education within the schools of Tanzania has not been as effective as desired. To be effective in “kicking AIDS out of Africa”, we need to re-evaluate the educational strategies being used.