Along with Capron High School in Illinois, they formed the original five members of the conference.
[1] In 1939, Palmyra joined after competing as an independent after their exit from the Southeastern three years prior.
Membership continued at ten for the next seven years, but the Southern Regional Conference quickly started to shed members in the late 1950s due to both schools leaving the conference and consolidation of rural school districts.
[8] Richmond-Burton High School took the same path as North Boone a year later, leaving the Southern Regional in 1957 to join them in the SHARK.
[13] Big Foot was to set to remain in the Southern Regional Conference due to their predecessors both being member schools, but Badger took Lake Geneva's place in the Southern Lakes Conference.