Interstate Eight Conference


The Interstate Eight Conference is an athletic conference of Illinois high schools that are members of the Illinois [High School Association]. The conference currently has six member schools throughout Northern Illinois that compete in 12 different sports.
The Interstate Eight began in 1979 and originally had eight schools—Coal City, Dwight, Marseilles, Plano, Reed-Custer, Seneca, Wilmington, and Yorkville. Sandwich soon entered the I-8 when Marseilles dropped out. In 1991, Yorkville was replaced by Lisle. In 2006 Herscher, Manteno, Peotone, and Westmont joined the conference. Despite the conference growing from eight to 12 teams, the conference name remained Interstate 8. Dwight left the conference prior to the 2014–15 season while Streator joined the conference. In 2019–20, Reed-Custer, Manteno, Peotone, Herscher, Wilmington, Seneca, Streator, Coal City, Westmont and Lisle left the conference leaving only Plano and Sandwich in the conference. That year, the conference added six schools from the soon to be defunct Northern Illinois Big 12 Conference. These included Kaneland, LaSalle-Peru, Morris, Ottawa, Rochelle, and Sycamore. These moves left Plano as the only remaining founding member of the conference.
In 2022, Sandwich High School and Plano High School announcing to leave the conference to join Kishwaukee River Conference starting in 2023–24 season. Plano was the final remaining original I8C member, completing nearly 45 seasons. This left the Interstate Eight with, ironically, only six schools. All of which are the former NI-Big 12 schools.
Most of the member schools are/were in rural/smaller towns. Former members Westmont and Lisle 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.
The Conference is divided into Large and Small divisions during football season and teams only play members of their division for the conference schedule. Baseball and softball are also divided into North and South divisions. In all other sports, the conference is undivided.

Members

There are six current members of the conference

Membership Timeline


DateFormat = yyyy
ImageSize = width:1000 height:auto barincrement:20
Period = from:1979 till:2025
TimeAxis = orientation:horizontal
PlotArea = right:20 left:0 bottom:50 top:5 #> to display a count on left side of graph, use "left:20" to suppress the count, use "left:20"<#
Colors = id:barcolor
id:line value:pink
id:bg value:white
id:Full value:rgb # Use this color to denote a team that is a member in all sports
id:FullxF value:rgb # Use this color to denote a team that is a member in all sports except for football
id:AssocF value:rgb # Use this color to denote a team that is a member for football only
id:AssocOS value:rgb # Use this color to denote a team that is a member in some sports, but not all
id:OtherC1 value:rgb # Use this color to denote a team that has moved to another conference
id:OtherC2 value:rgb # Use this color to denote a team that has moved to another conference where OtherC1 has already been used, to distinguish the two

PlotData=
width:15 textcolor:black shift: anchor:from fontsize:s
bar:1 color:Full from:1979 till:2019 text:Coal City
bar:2 color:Full from:1979 till:2014 text:Dwight
bar:3 color:Full from:1979 till:1985 text:Marseilles
bar:4 color:Full from:1979 till:2023 text:Plano
bar:5 color:Full from:1979 till:2019 text:Reed-Custer
bar:6 color:Full from:1979 till:2018 text:Seneca
bar:7 color:Full from:1979 till:2019 text:Wilmington
bar:8 color:Full from:1979 till:1991 text:Yorkville
bar:9 color:Full from:1985 till:2023 text:Sandwich
bar:10 color:Full from:1991 till:2019 text:Lisle
bar:11 color:AssocF from:2002 till:2006 text:Manteno
bar:11 color:Full from:2006 till:2019 text:
bar:12 color:AssocF from:2002 till:2006 text:Peotone
bar:12 color:Full from:2006 till:2019 text:
bar:13 color:Full from:2006 till:2019 text:Herscher
bar:14 color:Full from:2006 till:2018 text:Westmont
bar:14 color:FullxF from:2018 till:2019 text:
bar:15 color:Full from:2014 till:2019 text:Streator
bar:16 color:Full from:2019 shift: till:end text:Kaneland
bar:17 color:Full from:2019 shift: till:end text:LaSalle-Peru
bar:18 color:Full from:2019 shift: till:end text:Morris
bar:19 color:Full from:2019 shift: till:end text:Ottawa
bar:20 color:Full from:2019 shift: till:end text:Rochelle
bar:21 color:Full from:2019 shift: till:end text:Sycamore
ScaleMajor = gridcolor:line unit:year increment:2 start:1979
TextData =
fontsize:L
textcolor:black
pos: tabs:
text:^"I8C Membership History"
  1. > If the chart uses more than one bar color, add a legend by selecting the appropriate fields from the following six options Leave a blank line after the end of the timeline, then add a line with the selected values from the list, separated by a space. <#

State titles

Football

Football is based on an 8 class system since 2001.
  • Plano
  • Coal City
  • Seneca
  • Wilmington

Boys baseball

  • Lisle
  • Wilmington
  • Reed-Custer
  • Herscher

Wrestling

  • Wilmington
  • Sandwich
  • Reed-Custer

Boys basketball

  • Seneca

Boys golf

  • Dwight

Boys soccer

  • Lisle

Girls soccer

  • Manteno
  • Manteno

Competitive cheerleading

  • Dwight
  • Wilmington

Competitive Dance Team

  • Peotone

Boys cross country

Cross Country is based on a 3 class system since 2007.
  • Seneca
  • Kaneland

Girls cross country

Cross Country is based on a 3 class system since 2007.
  • Herscher

Girls track and field

  • Herscher

Girls softball

  • Coal City

Girls volleyball

  • Lisle

Scholastic Bowl

Lisle