Seventy-five high schools in Illinois rank among the nation's most challenging, according to the Washington Post.
The Washington Post's annual ranking assesses nearly 2,300 high schools across the U.S. based on a formula it calls the "Challenge Index" ratio, which is calculated by taking the total number of advanced placement, international baccalaureate and advanced international certificate of education tests administered at a given school in 2015 and dividing by the number of seniors who graduated that same year.
A ratio of at least 1.00 means a school had as many tests in 2015 as graduates, but only 10 percent of the roughly 22,000 public high schools in the U.S. reached that standard and earned a spot on the list, according to the Washington Post.
More about the methodology:
We do not include any magnet or charter high school that draws such a high concentration of top students that its average SAT or ACT score exceeds the highest average for any normal-enrollment school in the country. This year, that meant such schools had to have an average SAT score below 2023 or an average ACT score below 28.5 to be included on the main list.
The Challenge Index is designed to identify schools that have done the best job in persuading average students to take college-level courses and tests. It does not work with schools that have no, or almost no, average students. We put those schools on our Public Elites list.
Following are the Top 25 most challenging high schools in Illinois, along with each school's national rank, the percentage of graduates who passed at least one college-level test during their high school career -- referred to as equity and excellence (E&E), the percentage of students who come from families that qualify for subsidized lunch and the Challenge Index ratio.
*Denotes private high school
- National Rank: 858
- E&E: 50.7%
- Subs. Lunch: 12%
- Challenge Index: 2.732
24. J.S. Morton West High School | Berwyn
- National Rank: 852
- E&E: n/a
- Subs. Lunch: 81%
- Challenge Index: 2.742
23. Highland Park High School | Highland Park
- National Rank: 843
- E&E: 80%
- Subs. Lunch: 10%
- Challenge Index: 2.753
22. Cristo Rey St. Martin College Prep* | Waukegan
- National Rank: 769
- E&E: 25%
- Subs. Lunch: 88%
- Challenge Index: 2.904
21. Buffalo Grove High School | Buffalo Grove
- National Rank: 758
- E&E: 46.8%
- Subs. Lunch: 16.2%
- Challenge Index: 2.924
20. Elk Grove High School | Elk Grove
- National Rank: 705
- E&E: 48.1%
- Subs. Lunch: 33.5%
- Challenge Index: 3.014
19. Libertyville High School | Libertyville
- National Rank: 668
- E&E: 53.4%
- Subs. Lunch: 5.5%
- Challenge Index: 3.093
18. Hinsdale South High School | Darien
- National Rank: 667
- E&E: 43.1%
- Subs. Lunch: 32.2%
- Challenge Index: 3.098
17. Prospect High School | Mt. Prospect
- National Rank: 642
- E&E: 56.7%
- Subs. Lunch: 9.7%
- Challenge Index: 3.145
- National Rank: 579
- E&E: 76%
- Subs. Lunch: 32%
- Challenge Index: 3.306
- National Rank: 533
- E&E: 59.3%
- Subs. Lunch: 8%
- Challenge Index: 3.422
- National Rank: 526
- E&E: n/a
- Subs. Lunch: n/a
- Challenge Index: 3.431
13. John Hersey High School | Arlington Heights
- National Rank: 517
- E&E: 100%
- Subs. Lunch: 12.7%
- Challenge Index: 3.451
- National Rank: 489
- E&E: n/a
- Subs. Lunch: 94%
- Challenge Index: 3.626
- National Rank: 467
- E&E: 30%
- Subs. Lunch: n/a
- Challenge Index: 3.626
To see the Top 10 most challenging high schools in Illinois, click here.