State profile · IL

Illinois Public Schools

Every public school, district, and the headline NCES measures for Illinois — 865 districts, drawn straight from federal records.

3,845
Schools
1,844,783
Students
14.6:1
Avg ratio
—
Free lunch

The state in one line

Illinois runs 3,845 public schools across 865 districts, with a 14.6:1 average classroom and — of students on subsidized lunch.

3,845
public schools
865
school districts
14.6:1
avg student–teacher
—
free/reduced lunch

What the NCES Data Says About Illinois Schools

Illinois operates 3,845 public K-12 schools organised into 865 independent school districts serving 1,844,783 students, per the National Center for Education Statistics Common Core of Data 2024-25. The largest district, City of Chicago Sd 299, enrolls 321,666 pupils across 644 schools at $21,050 per student, while smaller rural districts can run fewer than a dozen campuses. This fragmentation — inherited from century-old township governance patterns in many states — is why per-pupil spending, class sizes, and programme availability vary dramatically inside a single state boundary.

Statewide, the average student-teacher ratio is 14.6:1, a useful benchmark for comparing any individual district or school on PlainSchools. The district table below is sortable by enrollment, school count, and per-pupil expenditure — the three fields that best predict a district's financial and demographic profile. For schools specifically, use the rankings links above to view per-category leaderboards covering spending, class size, best schools by composite quality score, chronic absenteeism, and funding-equity distribution within the state.

Every district figure here pulls from two distinct federal surveys: enrollment and demographic data come from the NCES Common Core of Data 2024-25 (school membership and directory), while per-pupil spending, teacher salaries, and federal/state/local revenue shares originate in the NCES F-33 School District Finance Survey (typically FY 2021-22). Civil-rights indicators — gifted enrollment, AP course counts, counselor staffing, chronic absenteeism, in- and out-of-school suspensions — come from the 2021-22 Civil Rights Data Collection. Cross-referencing these three sources is what lets PlainSchools produce composite scores and equity rankings that single-source tools cannot.

Illinois's average class size vs. every US state

Average students per teacher, state by state (lower means smaller classes)

15 smaller classes than 43% of 51 US states

11–12: 7 US states (14%). Below this entry. 12–13: 4 US states (8%). Below this entry. 13–14: 8 US states (16%). Below this entry. 14–15: 10 US states (20%). This entry sits in this band. 15–16: 5 US states (10%). Above this entry. 16–17: 4 US states (8%). Above this entry. 17–18: 4 US states (8%). Above this entry. 18–19: 5 US states (10%). Above this entry. 20–21: 1 US states (2%). Above this entry. 21–22: 1 US states (2%). Above this entry. 22–23: 1 US states (2%). Above this entry. 23–24: 1 US states (2%). Above this entry. This state 11 24 every US state, by average class size, bucketed by value

Each bar is a band; taller bars hold more US states. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source U.S. Department of Education — NCES Common Core of Data · 2024-25

Or browse all Illinois schools

Federal data — no proprietary formula. PlainSchools publishes the actual federal survey data — enrollment, staffing, finance, and demographics from NCES — without a composite rating on top. The insights below are computed directly from those datasets; every number traces to a cited source.

City of Chicago Sd 299 accounts for 17.4% of all Illinois K-12 enrollment

That concentration — well above the 8.4% national median for largest-district share — means state-level averages can mask substantial variation outside the dominant district. City of Chicago Sd 299 operates 644 schools serving 321,666 students, spending $21,050 per pupil. When one district dominates a state's K-12 footprint, its programmatic and budget decisions effectively set policy for a majority of the state's students.

Source: NCES Common Core of Data Local Education Agency (District) Universe Survey · 2024-25

Illinois per-pupil spending varies 6.5× across districts

Per-pupil spending in Illinois ranges from $8,375 (lowest district) to $54,037 (highest), a spread of $45,662. That spread reflects typical state-level variation between high-property-value suburbs and rural or low-tax-base districts. High-spending districts typically draw on higher property tax bases, a structural feature of state education finance under the federal Title I framework that sets the floor but not the ceiling.

Source: NCES F-33 School District Finance Survey Local Education Agency Finance Survey (F-33) · FY 2021-22

Illinois operates 865 school districts — among the most fragmented K-12 governance structures in the country

Each district has independent budgeting, hiring, and curriculum authority. The fragmentation predates modern county-level consolidation efforts and reflects 19th-century township governance patterns — a feature of states that organised public schooling around small civic units rather than centralised state systems. Per-pupil spending and accountability variations are largest in fragmented states because each district sets its own tax rate, contracts, and programme mix without state-level coordination above the regulatory floor.

Source: NCES Common Core of Data Local Education Agency Universe · 2024-25

Average Illinois student-teacher ratio is 14.6:1 — near the U.S. average of approximately 16:1

Student-teacher ratio is the simplest staffing metric reported on NCES Common Core of Data, but it does not capture push-in specialists, intervention staff, English Language Learner aides, special education co-teachers, or counseling and support staff. Variation between districts within the state is wider than the state-average figure suggests — large urban districts may run 20:1 while small rural districts run 10:1, both inside the same average. Class-load comparisons are most meaningful at the district or school level, not the state aggregate.

Source: NCES Common Core of Data — Public School Universe School-level enrollment and staffing · 2024-25

School Spending

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Schools ranked by per-pupil expenditure

District Spending

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Districts ranked by per-pupil expenditure

Largest Schools

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Schools ranked by student enrollment

Funding Equity

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Districts ranked by funding equity score

Best Student-Teacher Ratios

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Schools with the smallest class sizes

Best Schools

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Top-rated schools by quality score

Best Districts

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Top-ranked districts by quality score

Chronic Absenteeism

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Schools ranked by absenteeism rates

Affordable Districts

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Quality schools in affordable areas

Largest districts in Illinois

By total K-12 enrollment — NCES Common Core 2024-25

Top district = 17% of enrollment
City of Chicago Sd 299321,666Sd U-4635,082Rockford Sd 20527,442Indian Prairie Cusd 20425,687Plainfield Sd 20224,856Cusd 30020,443Cusd 30816,940Naperville Cusd 20316,073Valley View Cusd 365u15,187Schaumburg Ccsd 5414,966
# District Enrollment
1 City of Chicago Sd 299 Chicago 321,666
2 Sd U-46 Elgin 35,082
3 Rockford Sd 205 Rockford 27,442
4 Indian Prairie Cusd 204 Aurora 25,687
5 Plainfield Sd 202 Plainfield 24,856
6 Cusd 300 Algonquin 20,443
7 Cusd 308 Oswego 16,940
8 Naperville Cusd 203 Naperville 16,073
9 Valley View Cusd 365u Romeoville 15,187
10 Schaumburg Ccsd 54 Schaumburg 14,966
11 Waukegan Cusd 60 Waukegan 13,679
12 Springfield Sd 186 Springfield 13,066
13 Peoria Sd 150 Peoria 12,674
14 Aurora East Usd 131 Aurora 12,619
15 Mclean County Usd 5 Normal 12,409
16 Township Hsd 211 Palatine 12,270
17 Township Hsd 214 Arlington Heights 12,052
18 St Charles Cusd 303 Saint Charles 11,801
19 Cusd 200 Wheaton 11,638
20 Aurora West Usd 129 Aurora 11,211
21 Palatine Ccsd 15 Palatine 11,103
22 Champaign Cusd 4 Champaign 10,282
23 Joliet Psd 86 Joliet 9,553
24 Cicero Sd 99 Cicero 8,815
25 Huntley Comm Sch Dist 158 Algonquin 8,595
26 Elmhurst Sd 205 Elmhurst 8,299
27 Barrington Cusd 220 Barrington 8,173
28 J S Morton Hsd 201 Cicero 8,134
29 Decatur Sd 61 Decatur 7,974
30 Glenbard Twp Hsd 87 Glen Ellyn 7,836
31 Cons Hsd 230 Orland Park 7,691
32 Belvidere Cusd 100 Belvidere 7,558
33 Edwardsville Cusd 7 Edwardsville 7,274
34 Moline-Coal Valley Cusd 40 Moline 7,185
35 Crystal Lake Ccsd 47 Crystal Lake 7,109
36 Yorkville Cusd 115 Yorkville 6,937
37 Joliet Twp Hsd 204 Joliet 6,918
38 Dekalb Cusd 428 Dekalb 6,840
39 Lincoln Way Chsd 210 New Lenox 6,705
40 Evanston Ccsd 65 Evanston 6,383
41 Quincy Sd 172 Quincy 6,345
42 Round Lake Cusd 116 Round Lake 6,330
43 Rock Island Sd 41 Rock Island 6,204
44 Maine Township Hsd 207 Park Ridge 6,183
45 Harlem Ud 122 Machesney Park 6,178
46 Woodstock Cusd 200 Woodstock 6,159
47 Collinsville Cusd 10 Collinsville 6,140
48 Wheeling Ccsd 21 Wheeling 6,001
49 Granite City Cusd 9 Granite City 5,817
50 Alton Cusd 11 Alton 5,752
51 Comm Cons Sd 59 Elk Grove Vlg 5,707
52 Lake Zurich Cusd 95 Lake Zurich 5,626
53 Oak Park Esd 97 Oak Park 5,546
54 Chsd 218 Oak Lawn 5,490
55 Chsd 155 Crystal Lake 5,405
56 Arlington Heights Sd 25 Arlington Heights 5,316
57 Bremen Chsd 228 Midlothian 5,270
58 Batavia Usd 101 Batavia 5,260
59 Orland Sd 135 Orland Park 5,213
60 Geneva Cusd 304 Geneva 5,119
61 Glenbrook Hsd 225 Glenview 5,092
62 New Lenox Sd 122 New Lenox 5,050
63 Bloomington Sd 87 Bloomington 4,963
64 Downers Grove Gsd 58 Downers Grove 4,918
65 Central Cusd 301 Burlington 4,860
66 Belleville Twp Hsd 201 Belleville 4,802
67 Kankakee Sd 111 Kankakee 4,784
68 Chsd 99 Downers Grove 4,775
69 Danville Ccsd 118 Danville 4,754
70 Dunlap Cusd 323 Dunlap 4,736
71 Woodland Ccsd 50 Gurnee 4,695
72 Thornton Twp Hsd 205 South Holland 4,681
73 East St Louis Sd 189 East Saint Louis 4,679
74 Park Ridge Ccsd 64 Niles 4,671
75 Ball Chatham Cusd 5 Chatham 4,655
76 Niles Twp Hsd 219 Skokie 4,642
77 Minooka Ccsd 201 Minooka 4,499
78 Adlai E Stevenson Hsd 125 Lincolnshire 4,489
79 Proviso Twp Hsd 209 Forest Park 4,425
80 Urbana Sd 116 Urbana 4,423
81 Crete Monee Cusd 201u Crete 4,415
82 Wauconda Cusd 118 Wauconda 4,387
83 Glenview Ccsd 34 Glenview 4,317
84 Ccsd 62 Des Plaines 4,261
85 Maywood-Melrose Park-Broadview 89 Melrose Park 4,208
86 Mascoutah Cud 19 Mascoutah 4,152
87 Mchenry Ccsd 15 Mchenry 4,079
88 Kaneland Cusd 302 Maple Park 4,040
89 Troy Ccsd 30c Plainfield 4,012
90 Triad Cusd 2 Troy 3,991
91 O Fallon Ccsd 90 O Fallon 3,944
92 Galesburg Cusd 205 Galesburg 3,928
93 Dupage Hsd 88 Addison 3,919
94 Lockport Twp Hsd 205 Lockport 3,872
95 Hinsdale Twp Hsd 86 Hinsdale 3,843
96 Lyons Twp Hsd 204 La Grange 3,842
97 North Shore Sd 112 Highland Park 3,785
98 New Trier Twp Hsd 203 Northfield 3,779
99 Warren Twp Hsd 121 Gurnee 3,758
100 Marion Cusd 2 Marion 3,749

Showing top 100 of 865 districts by enrollment.

Source: NCES Common Core of Data As of 2024-25 Local Education Agency Universe Federal universe survey of all U.S. school districts

Largest Schools in Illinois

Adlai E Stevenson High School
Lincolnshire — high
4,758
students
Lane Technical High School
Chicago — other
4,604
students
Taft High School
Chicago — other
4,487
students
Waukegan High School
Waukegan — high
4,186
students
East High School
Aurora — high
4,020
students
Lyons Twp High Sch
La Grange — high
3,706
students
Lockport Township High Sch East
Lockport — high
3,678
students
West Aurora High School
Aurora — high
3,641
students
Evanston Twp High School
Evanston — high
3,560
students
Warren Township High School
Gurnee — high
3,537
students

Other States

Georgia
GA public schools
Hawaii
HI public schools
Idaho
ID public schools
Indiana
IN public schools
Iowa
IA public schools
Kansas
KS public schools

Side-by-side: Compare City of Chicago Sd 299 vs Sd U-46 → · Compare any two districts

Data sourced from NCES Common Core of Data (CCD) 2024-25, NCES F-33 School District Finance Survey, and Civil Rights Data Collection (CRDC) 2021-22.

Frequently Asked Questions

How many public schools are in Illinois?

Illinois has 3,845 public schools across 865 school districts, serving 1,844,783 students.

What is the average student-teacher ratio in Illinois?

The average student-teacher ratio in Illinois public schools is 14.6:1. This varies by district — use the district table below to compare.

What is the largest school district in Illinois?

The largest school district in Illinois is City of Chicago Sd 299 with 321,666 students across 644 schools.

Why does per-pupil spending vary so much across Illinois districts?

Illinois districts spend between $8,375 and $54,037 per pupil — a 6.5× range. Most U.S. states fund schools through a mix of state aid (typically 40-60%), local property tax (30-50%), and federal Title I (5-15%). Districts in higher property-value areas raise more per pupil from local taxes, while state aid is intended to partially equalise but rarely closes the full gap. The federal F-33 finance survey reports actual current expenditures including instructional and support services.

Read our methodology — how this data is sourced, computed, and verified.

Top schools in Illinois by enrollment

Largest K-12 public schools by total students enrolled

students

What this shows The largest public schools in Illinois by enrollment — often statewide virtual academies or large consolidated campuses, so size here reflects reach, not quality.

Source NCES Common Core of Data (CCD) As of 2024-25

Source: National Center for Education Statistics (NCES) Common Core of Data (CCD) — Public school universe · 2023-2024 Public K-12 school enrollment, demographics, and operational data; collected annually by NCES from state education agencies.