The core of the SCC has always been built around the triangle of Albia, Centerville and Bloomfield, 3 schools roughly the same size with strong rivals between each of them. Chariton and Eddyville have developed into the fourth and five schools in the group. All are roughly the same size, easy drive time from each other.
Other schools have come and gone as they have grown or shrank like Winterset, Knoxville, PCM. Ocseola has always been stuck out by itself with no where to go, so they stick with the conference. Cardinal joined a few years ago, have no clue why, outside of softball they just cannot compete. Schools to the east and west are too small to join the SCC and the schools to the north are too large.