Little is considered taboo in the colorful new ads, which depict everything from general condom use and masturbation to more severe topics like teen pregnancy and female genital mutilation. While the murals may often be done in a tongue-in-cheek manner, Tanzania's statistics are considerably less so. The current HIV rate hovers at about 6 percent, while 40 percent of 18-year-old girls are already mothers or currently pregnant.

Officials say the occasionally racy murals are already proving effective, and many local schools are opting to follow suit with their own sex ed walls. "If you use a photograph, people don't identify with the person," said Alex Ngaiza, HIV program manager at the health communication organization PSI. "But with a mural, everyone can relate."