▁Amb raw ▁Valley ▁Conference ▁( 1 9 4 5 - 1 9 5 5 ) ▁Big ▁ 7 ▁( 1 9 1 9 - 1 9 3 9 ) ▁Big ▁ 8 ▁( 1 9 4 0 - 7 0 ) ▁Big ▁ 9 ▁( 1 9 7 1 - 8 1 ) ▁Big ▁R ivers ▁Conference ▁( football - only ) ▁( 1 9 9 9 - 2 0 1 2 ) ▁Bi - Count y ▁Conference ▁( 1 9 1 7 - 1 9 1 9 ) ▁Bi - Count y ▁Conference ▁( 1 9 7 0 s - 1 9 9 8 ) ▁Black h awk ▁Conference ▁( 1 9 3 4 - 1 9 9 0 ) ▁Bureau ▁Valley ▁Conference ▁( 1 9 7 0 s - 1 9 9 0 s ) ▁Capit ol ▁Conference ▁( 1 9 6 4 - 1 9 8 2 ) ▁C eno is ▁Conference ▁( 1 9 6 3 - 1 9 6 9 ) ▁Central ▁Conference ▁( 1 9 5 6 - 1 9 5 8 ) ▁Central ▁Egypt ian ▁Conference ▁( 1 9 2 9 - 1 9 4 0 ) ▁Ch ic ag ol and ▁P rep ▁Conference ▁( 1 9 6 1 - 1 9 6 9 ) ▁Co al ▁B elt ▁Conference ▁( 1 9 4 6 - 1 9 5 6 ) ▁Cook ▁County ▁High ▁School ▁League ▁( 1 8 8 9 – 1 9 1 3 ) ▁Corn ▁B elt ▁Conference ▁( 1 9 5