| Boys Basketball Undefeated Teams | |||
| Year | Class | School | Wins |
|---|---|---|---|
| 2010 | 8-3A | Casey-Westfield | 28 |
| 2010 | 8-4A | Springfield Grant | 27 |
| 2009 | 7-4A | Morton JHS | 27 |
| 2009 | 7-3A | Monmouth-Roseville JHS | 23 |
| 2007 | 8-1A | Catlin | 25 |
| 2007 | 7-3A | Wenona Fieldcrest | 28 |
| 2006 | 7AA | Danville North Ridge | 27 |
| 2005 | 7AA | Cahokia Wirth | 16 |
| 2005 | 8AA | Bloomington JHS | 27 |
| 2003 | 7A | Monmouth ICS | 24 |
| 2003 | 8AA | Harvey Brooks | 29 |
| 2002 | 7AA | Bloomington JHS | 24 |
| 2001 | 7A | Mt. Pulaski | 25 |
| 2001 | 8AA | Bloomington JHS | 26 |
| 2000 | 8AA | Charleston | 25 |
| 1998 | 7AA | Pekin Edison | 24 |
| 1997 | 8AA | Pleasant Plains | 27 |
| 1997 | 7AA | Dixmoor Rosa Parks | 18 |
| 1995 | 8A | Nauvoo-Colusa | 23 |
| 1994 | 7AA | Pontiac | 21 |
| 1993 | 7A | Hartsburg-Emden | 24 |
| 1993 | 8A | Toluca Fieldcrest West | 24 |
| 1992 | 8AA | Springfield Washington | 23 |
| 1991 | 8AA | Quincy | 22 |
| 1991 | 7AA | Springfield Washington | 22 |
| 1989 | 8AA | Pekin Broadmoor | 24 |
| 1989 | 7A | Dieterich | 23 |
| 1988 | 7AA | Springfield Franklin | 23 |
| 1988 | 8AA | Dixmoor Rosa Parks | 27 |
| 1987 | 8A | Griggsville | 24 |
| 1987 | 8AA | Pekin Broadmoor | 24 |
| 1985 | 7AA | Dixmoor Rosa Parks | 22 |
| 1985 | 8A | Chandlerville | 23 |
| 1982 | A (Hvy.) | Washington Central | 26 |
| 1981 | C (7th) | Dixmoor Rosa Parks | 20 |
| 1981 | AA (Hvy.) | Cahokia Wirth | 23 |
| 1981 | A (Hvy.) | Kincaid | 25 |
| 1981 | B (Lt.) | Rantoul St. Malachy | 21 |
| 1980 | A (Hvy.) | Washington Central | 26 |
| 1980 | B (Lt.) | Mt. Pulaski | 25 |
| 1980 | C (7th) | Cahokia Wirth | 21 |
| 1979 | B (Lt.) | Pekin Edison | 22 |
| 1979 | A (Hvy.) | Griggsville | 25 |
| 1978 | B (Lt.) | Wheeler West | 11 |
| 1978 | A (Hvy.) | Stonington | 23 |
| 1978 | AA (Hvy.) | Joliet Washington | 24 |
| 1977 | C (7th) | Peoria Trewyn | 16 |
| 1976 | C (7th) | Kankakee King | 10 |
| 1975 | B (Lt.) | Pekin Edison | 24 |
| 1975 | C (7th) | Bartonville Monroe | 13 |
| 1974 | C (7th) | Kankakee King | 11 |
| 1971 | A (Hvy.) | Pekin Edison | 24 |
| 1968 | A (Hvy.) | Rantoul Eater | 22 |
| 1967 | B (Lt.) | Pekin Edison | 23 |
| 1966 | A (Hvy.) | Pittsfield Higbee | 23 |
| 1966 | B (Lt.) | Peoria Woodrow Wilson | 25 |
| 1965 | A (Hvy.) | Normal Chiddix | 22 |
| 1964 | A (Hvy.) | Chillicothe | 23 |
| 1963 | B (Lt.) | Rantoul Eater | 24 |
| 1963 | A (Hvy.) | Lincoln | 22 |
| 1962 | A (Hvy.) | Lincoln | 24 |
| 1961 | A (Hvy.) | Lincoln | 24 |
| 1959 | A (Hvy.) | Mahomet-Seymour | 22 |
| 1958 | B (Lt.) | Carmi | 16 |
| 1956 | B (Lt.) | Paris Mayo | 22 |
| 1953 | A (Hvy.) | Pekin Washington | |
| 1951 | B (Lt.) | Monticello Washington | 23 |
| 1944 | B (Lt.) | Canton Ingersoll | |
| 1941 | B (Lt.) | Arthur | 26 |
| 1938 | B (Lt.) | Morton JHS | 21 |
| 1938 | B (Lt.) | Normal Central | 33 |
| 1936 | B (Lt.) | Morton JHS | |
| 1930 | B (Lt.) | Bloomington Franklin | 26 |
Class HistoryFrom 1930 to 1972, there were two classes of basketball, Class A (Heavyweight) and Class B (Lightweight). An additional class was added in 1973--Class C (7th Grade). The Heavyweight and Lightweight classes were based on age, height and weight. From 1977-1984, the Heavyweight class was divided into two classes based upon enrollment--(A & AA). From 1985-2006, the Association adopted the format of 7th and 8th grade play based upon a school's enrollment (7A, 7AA, 8A and 8AA). Starting in 2007, the Association adopted a four class system in each grade level (7-1A, 7-2A, 7-3A, 7-4A, 8-1A, 8-2A, 8-3A and 8-4A). The current classification system assigns 25% of the schools to each of the four classes. |