After the last court proceedings on May 15, one of the teenagers was sent to Sterkfontein Psychiatric Hospital for mental observation.
The boys, who cannot be named because they are minors, were arrested in connection with the murders of Thandeka Moganetsi, 15, and Chwayita Rathazayo, 16. The girls were found dead in a field in Dobsonville, Soweto, in February.
They were both wearing George Khoza Secondary School uniforms and had cuts on their hands and necks. Three black candles and two razor blades were found at the scene, leading to speculation that the murders were related to a satanic ritual.