Mid-State Conference (IHSAA) Former Members Former Members

| School | Location_ | Mascot | County | Year_Joined | Year_Left | Conference_Joined |
|---|---|---|---|---|---|---|
| Avon | Avon | Orioles | 32 Hendricks | 1974 | 2000 | Hoosier Crossroads |
| Beech Grove | Beech Grove | Hornets | 49 Marion | 1978 | 2005 | Indiana Crossroads |
| Brownsburg | Brownsburg | Bulldogs | 32 Hendricks | 1942 | 1967 | Sagamore |
| Center Grove | Greenwood | Trojans | 41 Johnson | 1956 | 1981 | Central Suburban |
| Danville | Danville | Warriors | 32 Hendricks | 1942 | 1978 | West Central |
| Decatur Central | Indianapolis | Hawks | 49 Marion | 1942 | 1971 | Central Suburban |
| Lawrence Central | Indianapolis | Bears | 49 Marion | 1942 | 1949 | Capital District |
| Speedway | Speedway | Sparkplugs | 49 Marion | 1942 | 1999 | West Central |