Interstate Eight Conference
The Interstate Eight Conference (I-8) has 12 schools in Illinois that are members of the conference. The Interstate Eight originally had 8 schools—Coal City, Dwight, Yorkville, Plano, Reed-Custer, Sandwich, Seneca and Wilmington. In 1991, Yorkville was replaced by Lisle. In 2006 Herscher, Manteno, Peotone and Westmont joined the conference. This conference is one of the most competitive conferences in the state. The Conference is divided into Large and Small divisions during football season. In all other sports, the conference is undivided.
Most of the member schools are in rural towns. Westmont and Lisle Senior High Schools are Suburbs of Chicago but enrollments are small in size. Westmont's population is divided between the varying schools in the area, including High Schools in Darien, Woodridge, Hinsdale, Bolingbrook, Naperville, Lisle, Lombard, and Glen Ellyn. Lisle's enrollment is small, due to Lisle's relatively small size as a city, as well as being located East of Naperville, which has at least four High Schools in the immediate vicinity, as well as the Glenbard schools and Wheaton-Warrenville South all being within a close proximity to the High School.
Members of the I-8 Conference are all members of the Illinois High School Association (IHSA). The conference was recently changed with Reed-Custer moving into the small division and Plano moving into the large division. Streator High School is entering the conference, and Dwight High School is leaving the conference starting in the 2014-2015 season. Streator will be the largest of the 12 schools, and that may change the current divisional arrangement of the schools in the conference.
Large Division
- Coal City High School Coalers
- Streator Bulldogs
- Manteno High School Panthers
- Peotone High School Blue Devils
- Plano High School Reapers
- Sandwich Community High School Indians
Small Division
- Herscher High School Tigers
- Lisle Sr. High School Lions
- Reed-Custer High School Comets
- Seneca High School Fighting Irish
- Westmont High School Sentinels
- Wilmington High School Wildcats
Football
Football is based on an 8 class system since 2001.
- Plano (2006 3A, 2007 3A)
- Coal City (1993 2A)
- Seneca (1990 2A)
- Wilmington (2014 3A)
Boys baseball
- Lisle (2013 2A)
- Wilmington (2003, 2005)
- Reed-Custer (1985)
- Herscher (1999) (2015)
Wrestling
- Wilmington (2007, 2008, 2009)
- Sandwich (1991, 1997, 1999, 2001)
- Reed-Custer (2010,2012)
Boys basketball
- Seneca (2005–06 A)
Boys golf
- Dwight (1980)
Boys soccer
- Lisle (2010 1A)
Girls soccer
- Manteno (2009 1A)
Competitive cheerleading
- Dwight (2013)
Competitive Dance Team
- Peotone (2012 1A)
Boys cross country
Cross Country is based on a 3 class system since 2007.
- Seneca (1989 A)
Girls cross country
Cross Country is based on a 3 class system since 2007.
- Herscher (1991 A, 1992 A, 1996 A)
Girls track and field
- Herscher (1996)
Girls softball
- Coal City (2010)
Girls volleyball
- Lisle (1985)
Scholastic Bowl
Lisle (2011, 2012)