The 2004 Illinois High School Association (IHSA) State Championship Tournaments ended the eighteenth State Championship Series conducted in Scholastic Bowl by the IHSA. It was the thirteenth season in which there were separate State Championship Tournaments held for small schools (Class A) and large schools (Class AA). For the eighth year, both tournaments were held at the Peoria Civic Center.
Teams were assigned to one of eight sectionals within each class. Teams were seeded by the coaches, and teams would then be assigned to one of four Regionals within each Sectional. The winners of the regionals would advance to their respective sectional tournaments, where they would play a three match round robin to determine a winner. The determination of the geographic boundaries of the Sectional was arbitrarily decided by the IHSA Office.
Each round was comprised of 30 toss-ups and accompanying bonus questions.
In the State Championship Tournament, teams would be randomly assigned to pools of four, and play a three match round robin. The winners of each pool would advance to the Championship Match, and the runners-up in each pool would advance to play for third place. Ties were broken by head-to-head results or total points scored (in the event of a three way tie)
The top four teams earned trophies and medals for team members, coaches, principals, and activities directors. The trophies were of the design smaller than that of the athletic trophies given out by the IHSA.
For the fourth year, the questions were written by a group of retired coaches and person from other states.
The Latin School swept through their pool with a 3-0 record. Galena went 2-1 to advance to the third place match.
Carterville swept through their pool with a 3-0 record. Rockridge went 2-1 to advance to the third place match.
Wheaton North swept the pool easily to advance to the Championship Match. Fenwick went 2-1 and advance to play for third place.
Stevenson swept the pool to advance to the Championship Match. Auburn went 2-1 and advance to play for third place.
- As Wheaton North capped its third consecutive championship (which Stevenson would end next year), The Latin School was winning the first of what would become a streak of three consecutive state titles.
- The Wheaton North championship capped what could be considered the best year by any team in Illinois history. Paul Gauthier was the lone All-State player, and led the Falcons to a 95-1 record.
- The MacArthur Generals were also back in the State Championship Tournament after a five year absence. They were led by their junior phenom Donald Taylor.