According to the report, the study ranks schools through an index formula that is a simple ratio: the number of Advanced Placement, International Baccalaureate and Advanced International Certificate of Education tests given at a school each year, divided by the number of seniors who graduated that year. A ratio of 1.000 means the school had as many tests as graduates.
Also noted are the percentage of students who come from families that qualify for lunch subsidies and the percentage of graduates who passed at least one college-level test during their high school career, called equity and excellence, according to the report.
Horace Greeley High School received an index score of 3.371 with its 97-percent four-year graduation rate, average SAT score of 1,900, an average ACT score of 29.0 and an offering of 16 Advanced Placement courses.
Horace Greeley also was ranked the 38th-most challenging school in the Northeast region and 370th nationally.
City Honors in Buffalo was ranked the most challenging school in New York State with an index of 9.121. American Indian Public Charter School in Oakland, Calif., was named the most challenging school in America with an index of 21.909 in the Post's study.
The top 10 most-challenging high schools in Westchester County, according to the study are:
1. Bronxville High School (4.933)
2. Rye High School (4.220)
3. Yonkers High School (4.212)
4. Harrison High School (4.205)
5. Irvington High School (3.882)
6. Dobbs Ferry High School (3.537)
7. Horace Greeley High School, Chappaqua (3.371)
8. Croton-Harmon High School, Croton (3.349)
9. Edgemont High School, Scarsdale (3.321)
10. Rye Neck High School, Mamaroneck (3.155)
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