As of 2015, Illinois high school boys' basketball tournament records include game-highs of 56 points, 27 rebounds, 15 assists and 12 blocked shots. The IHSA does not track postseason statistical records at the regional and sectional levels of play, and it only recognizes super-sectional (quarterfinal) records prior to 2008.
Lincolnshire Stevenson's Jalen Brunson poured in the record 56 points in a Class 4A semi-final contest versus Chicago Whitney Young. Fernando Bunch of Chicago Providence St. Mel dished out the 18 assists in a 1985 Class A super sectional versus Dwight High. Kevin Washington of Petersburg Porta hauled in 27 rebounds in a 1973 Class A quarterfinal clash against Ridgway High. Walter Downing of New Lenox Providence Catholic recorded the 12 blocks in a 1978 Class A quarterfinal contest against Ottawa Marquette.
The IHSA places schools into one of four classes, 1A, 2A, 3A or 4A, based on student enrollment. The state tournament includes the four teams in each class that advance by winning their respective regional, sectional and super-sectional matches. Prior to 2008, the state tournament only had two classes: A and AA. Individual statistical records are listed on the IHSA website for each of the four current and two defunct classes. Those from super-sectional contests prior to 2008 on the website are given a 'quarterfinal' designation.