The health and education ministries and the United Nations sponsored a nationwide contest for students to design the dispenser. Three potential models were selected on Friday, the government news agency Agencia Brasil said.
Condom machines are to be installed in 100 public schools in 2008, officials said.
The head of the National Program of Sexually Transmitted Diseases, Mariangela Simao, said part of the project is educational and aims not to "banalize" the use of condoms. She said 100,000 schools were involved with the anti-AIDS program.
Health Minister Jose Gomes Temporao this week said young Brazilians between 13 and 24 were the target of Brazil's anti-AIDS campaign this year. Nearly 70,000 cases of AIDS were registered among Brazilians under 24, or about 16 percent of the cases reported in the country, according to the anti-AIDS program.
Brazil provides free AIDS drugs to anyone who needs them and has aggressively pushed drug manufacturers to lower prices.