Otago Boys' beat Southland Boys' 28-10 to qualify for the final.
In the middle four, Dunstan HS beat Otago Boys' High School second XV 19-17 while Mount Aspiring College beat Waitaki Boys' High School 41-19.
In the bottom four, the combined co-ed schools team had its second win of the season, defeating St Kevin's College 16-10.
Wakatipu beat South Otago HS 22-12 to be top of the bottom four.
The final round is next Saturday with finals to be played on August 17.