EDIT: A more recent announcement from the IHSA concerning high school athletics was issued on November 19 and is linked HERE.
For the current school year, the IHSA (Illinois High School Association) has rearranged the athletics schedules for many sports. There will be FOUR seasons: Fall, Winter, Spring and Summer extending across these dates, though all sports are currently paused (as of mid-December):
Fall: August 10 to October 24
Winter: November 16 to February 13
Spring: February 15 to May 1
Summer: May 3 to June 26
Sseveral sports will shift to new seasons, including football, boys soccer, and girls volleyball moving from the fall to the spring. IHSA boys and girls golf, girls tennis, cross country and girls swimming & diving will remain as fall sports. More information at this LINK.- scroll down the page for a table listing various sports and their season.