South Junior High is located in the southern portion of Boise. It is one of eight junior high schools in the Independent School District of Boise City. Construction on the original building was completed in 1948 and the school campus more than doubled over the years. Classrooms were added to meet the needs of an ever expanding student body and in 1962 a cafeteria and three additional classrooms were added. The last addition to the original structure occurred in 1972 when the Art Building was completed.

In 2008 South was relocated into a new, spacious and modern building on Cassia Street, around the corner from the original building. The new 140,000 square foot school has 38 classrooms, science labs, specialty use rooms, a library/media center with 52 computer spaces, a performance gymnasium, a practice gymnasium and an auditorium that seats over 900.

The original building has been torn down, but the Art Deco section of the library wall has been preserved and will become a portion of an amphitheater/interpretive plaza.

Adjacent to the school are 2 football fields, one full sized and the other a practice football field, 2 outside basketball courts, 4 tennis courts, a small city park, and a Boise City swimming pool.