Enrollments listed are official ones as of September 30, 2015. That is the State Board of Education's official enrollment day for every school in Illinois. We use the school's K-8 figure and do not count the pre-K numbers. For junior highs and middle schools we figure in their feeder schools in order to obtain the K-8 total.
These enrollments are used to determine classes for each sport until November of the next year.
| 2016-17 Boys Basketball Enrollments | ||||
|---|---|---|---|---|
| CLASS L | CLASS M | |||
| Collinsville | 4308 | Wolf Branch | 765 | |
| Mascoutah | 2600 | Carlyle | 746 | |
| Marion | 2535 | Millstadt | 743 | |
| Triad | 2494 | Johnston City | 726 | |
| Highland | 1860 | Anna | 723 | |
| Carriel-O'Fallon | 1821 | Sparta | 715 | |
| Central-Belleville | 1798 | Trico | 706 | |
| Waterloo | 1751 | Breese | 647 | |
| Fulton-O'Fallon | 1705 | Pontiac | 647 | |
| Herrin | 1639 | Unity Point | 624 | |
| Richland County-Olney | 1532 | Fairfield | 621 | |
| Massac County | 1522 | Chester | 592 | |
| Carterville | 1513 | Red Bud | 582 | |
| West-Belleville | 1486 | Christopher | 552 | |
| Casey-Mt.Vernon | 1386 | Joseph Arthur-O'Fallon | 550 | |
| Murphysboro | 1376 | Gallatin County | 525 | |
| Carbondale | 1364 | Nashville | 525 | |
| Harrisburg | 1345 | Pinckneyville | 521 | |
| Whiteside-Belleville | 1251 | Smithton | 515 | |
| Centralia | 1230 | Lebanon | 468 | |
| West Frankfort | 1169 | Norris City Omaha-Enfield | 465 | |
| Benton | 1066 | Sesser-Valier | 438 | |
| Belle Valley | 996 | Albion | 431 | |
| Carmi-White County | 978 | Adams-Creal Springs | 417 | |
| DuQuoin | 972 | Vienna | 405 | |
| Salem | 928 | South Central | 393 | |
| Mt.Carmel | 911 | Hardin County | 391 | |
| Wesclin | 889 | Goreville | 383 | |
| Flora | 871 | Zeigler-Royalton | 379 | |
| Hamilton County | 860 | Jonesboro | 378 | |
| Eldorado | 785 | Marissa | 359 | |
| Emge | 772 | Wayne City | 357 | |
| CLASS S | ||||
| Okawville | 355 | St.Andrew Co-op/M'boro | 197 | |
| Aviston | 347 | Iuka | 194 | |
| Pope County | 341 | Ewing-Northern | 193 | |
| Crab Orchard | 337 | Odin | 188 | |
| Signal Hill | 328 | St.John-Lutheran-Red Bud | 183 | |
| Rome | 323 | Kell-Farrington Co-op | 179 | |
| Cobden | 324 | St.Paul-Highland | 179 | |
| Woodlawn | 322 | New Hope | 179 | |
| Meridian | 311 | Joppa-Maple Grove | 176 | |
| Sandoval | 311 | 1st Baptist Academy-OF | 173 | |
| Valmeyer | 308 | Patoka | 172 | |
| New Athens | 304 | West Salem | 166 | |
| Egyptian | 303 | Unity Christian-Energy | 164 | |
| Steeleville | 292 | Jasper | 161 | |
| Carrier Mills | 286 | Opdyke Belle-Rive | 161 | |
| Galatia | 279 | Cypress-Buncomb Co-op | 159 | |
| Central City | 278 | Altamont Lutheran | 158 | |
| Albers-Damiansville Co-op | 275 | Bartelso | 155 | |
| Cairo | 272 | Tr.Lu.Hoyleton-G.Pr. Co-op | 155 | |
| OLMC-Herrin | 266 | Pinckneyville Cons. #204 | 151 | |
| Cisne | 263 | Willow Grove | 150 | |
| Century | 262 | Evansville | 147 | |
| Field | 256 | Prairie DuRocher | 147 | |
| Bluford | 255 | Coulterville | 146 | |
| Elverado | 254 | St.Rose | 143 | |
| Selmaville | 252 | Ashley | 142 | |
| Clay City | 241 | Tr. Lu.N'ville & O'ville Co-op | 142 | |
| Good Shepherd-Collinsville | 241 | St. John-Chester | 134 | |
| All Saints Academy-Breese | 240 | Lick Creek | 126 | |
| Summersville | 239 | St. Mary's-Mt.Carmel | 119 | |
| Bethel-McClellan Co-op | 237 | St.Mary'-VCA Co-op/MTV | 119 | |
| Spring Garden | 237 | Allendale | 117 | |
| Germantown | 232 | Trinity Lutheran-Centralia | 116 | |
| Holy Trinity-Fairview Hts. | 231 | Geff | 98 | |
| Raccoon | 231 | New Hebron | 98 | |
| Tamaroa-St.Bruno Co-op | 223 | New Horizon-Centralia | 95 | |
| St.Boniface-Edwardsville | 220 | St.Libory | 86 | |
| Waltonville | 216 | St.Teresa-VCA Co-op/Salem | 83 | |
| Dongola | 215 | Akin | 82 | |
| Shawnee | 215 | Oakdale | 79 | |
| Irvington-N.Wamac Co-op | 213 | Trinit Luth.-Hoffman | 76 | |
| St.Joe-Olney | 213 | St.Mary-Centralia | 72 | |
| Thompsonville | 208 | St.Peter | 72 | |
| Blessed Sacrament-B'ville | 206 | St.Marks Luth.-Steeleville | 71 | |
| Grayville | 205 | St. Mary's Cath.-Chester | 70 | |
| New Simpson Hill | 204 | St.Ann Cath.-Nashville | 68 | |
| Giant City | 199 | St.John Cath.-Red Bud | 56 | |
| DeSoto | 198 | St.John-West Frankfort | 53 | |
