| Event | Rank | Mark | By | Meet |
| | | National Elites above. State Elites below | | |
| B-300H | 1 | 39.09 | McConico, Jaylan (2016) (Bolingbrook, IL) | Palatine Relays(IL), 2015-05-02(#1) |
| B-300H | 2 | 39.12 | Porter, Jake (2016) (Lockport Township , IL) | Dick Beebe Track Classic(IL), 2015-04-18(#2) |
| B-300H | 3 | 39.41 | Mitchell, Demtrtrus (2015) (Thornton Township, IL) | John Bell Invitational(IL), 2015-04-18(#1) |
| B-300H | 4 | 39.72 | Elbert, Paris (2017) (Thornton Township, IL) | IL 3A Homewood-Flossmoor Boys Sectional(IL), 2015-05-21(#2) |
| B-300H | 5 | 39.89 | Brock, Ryan (2015) (Lockport Township , IL) | IL 3A Boys State Prelims(IL), 2015-05-29(#12) |
| B-300H | 6 | 39.91 | Faulkner, Baron (2015) (Thornwood, IL) | Dick Beebe Track Classic(IL), 2015-04-18(#3) |
| B-300H | 7 | 40.44 | Rawls, Treyonne (2016) (Thornridge, IL) | IL 2A Hillcrest Boys Sectional(IL), 2015-05-22(#3) |
| B-300H | 8 | 40.49 | Spears, Marquis (2015) (Bradley-Bourbonnais, IL) | IL 3A Homewood-Flossmoor Boys Sectional(IL), 2015-05-21(#4) |
| B-300H | 9 | 40.62 | Smith, Fred (2015) (Homewood-Flossmoor, IL) | Dick Beebe Track Classic(IL), 2015-04-18(#5) |
| B-300H | 10 | 41.47 | Wagner-Zbonski, Steven (2017) (Carl Sandburg, IL) | Southwest Suburban Blue Boys Conference Meet(IL), 2015-05-14(#4) |
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| | | See more performances for B-300H | | |
