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Largest Illinois 草榴社区 High Schools

The average private high school in Illinois has 239 students (2026-27).

The largest private high school in Illinois is American School, with 6,319 students.

Quick Facts (2026-27)

# IL Schools Ranked: 377
Top 20 Range (Students): 803鈥�6,319
IL School Avg.: 239
National School Avg.: 244

Quick Facts (2026-27)

# IL Schools Ranked: 377
Top 20 Range (Students): 803鈥�6,319
IL School Avg.: 239
National School Avg.: 244

Illinois Average Students Per School (Trends)

View Data

Year	Illinois (IL) avg
2025	238
2024	230
2023	248
2022	255
2021	247
2020	233
2019	252
2018	243
2017	239
2016	238
2015	230

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Note: Data may not be displayed on any public-facing website or service that replicates or resembles a school search or review portal without prior written permission. See our Terms of Service.

Show school map 鈥� Illinois (students range: 803鈥�6,319, avg 239)

School Size Range: 645 6,319 Avg. School Size: 1,124

Frequently Asked Questions

What is the Illinois average private high schools student size?

The Illinois average private high schools student size is 239 for 2026-27.

What are the private high schools with the largest student size in Illinois?

The top ranked private high schools in Illinois include American School, University of Chicago Laboratory Schools and Loyola Academy.

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