Research · High schools · October 2026
The largest public high schools in America, by grade 9-12 enrollment
As of October 2026: Brooklyn Technical High School in Brooklyn, New York is the largest public high school in the country, with 5,848 students in grades 9-12. Conroe High School in Texas is second at 5,252, and Carmel High School in Indiana third at 5,239.
The table holds the biggest public high schools in the federal enrollment file. Virtual schools are left out, so online academies with large rolls do not appear.
Analysis: Test Prep Gurus (High School Reach, highschoolreach.com), October 2026. Figures and the table may be quoted with attribution to Test Prep Gurus.
The findings, in plain English
One school sits clear at the top. Brooklyn Technical High School enrolls 5,848 students in grades 9-12. The next three are close together: Conroe High School in Texas at 5,252, Carmel High School in Indiana at 5,239 and Allen High School in Texas at 5,206.
Texas appears here more than any other state. Houston and its suburbs show up again and again: North Shore Senior High at 4,284, Elsik High School at 4,057, Summer Creek High School at 3,972, Hastings High School at 3,786 and Dobie High School at 3,692. Katy alone puts Seven Lakes High School and Cinco Ranch High School on the list.
Even the smallest school here is very large. Midwood High School in Brooklyn, the last school in the table, enrolls 3,657 students in grades 9-12. Granada Hills Charter in California, at 4,614, is the only charter school on the list. Every other one is a regular district high school.
The largest public high schools in America
Ranked by students in grades 9-12. Each school name links to its page.
Enrollment is grades 9-12 in the federal Common Core of Data for 2023-24, the latest federal file; a school's own site may show a newer number. Virtual schools are left out, so online academies that report very large rolls do not appear, and private schools are not in this file. Schools are ranked by their grade 9-12 count.
Why these schools got so big
Two different stories produce a school this size. One is a fast-growing suburb that builds one very large high school instead of three. Conroe, Allen, Prosper and Carmel are in that group. The other is a city magnet or exam school that draws from the whole district, which is how Brooklyn Technical High School, Lane Technical High School and Francis Lewis High School got here.
Size by itself is not good or bad news. A very large school can run a long AP list, a dozen sports and several languages that a small school cannot. The same school can also be a place where a quiet ninth grader is never noticed.
What the enrollment number covers
The figure is the count of students in grades 9-12 at that one campus, as the district filed it with the federal government for 2023-24. It is not the district total, and it does not include a middle school that shares the name or the site. A school's own site may show a newer number for this year, and the gap is usually small.
What a family should do with this
If your student is headed to a school on this list, the question is not size but structure. Find out how ninth graders are grouped, whether there are smaller academies or houses inside the building, and how many students each counselor carries. That last number sits on the school's page on Reach.
Then read the course list rather than the brochure. A big school usually offers more AP courses and more dual enrollment, and both of those sit on the school's page too. If they are thin at a school this large, that is the real finding.
Questions parents ask
What is the biggest high school in the United States?
Brooklyn Technical High School in Brooklyn, New York is the largest public high school in the country, with 5,848 students in grades 9-12.
Is a very large high school bad for my child?
A very large school can run a long AP list, a dozen sports and several languages that a small school cannot. The same school can also be a place where a quiet ninth grader is never noticed.
Are any charter schools on this list?
Granada Hills Charter in California, at 4,614, is the only charter school on the list.
Method & sources: Enrollment is the sum of grades 9 through 12 at each campus in the federal Common Core of Data for 2023-24, the latest federal file. The population is public and charter high schools; virtual schools are excluded, so online academies with very large reported rolls do not appear, and private schools are not in this file. Schools are ranked by that grade 9-12 count, largest first. A school's own site may publish a newer figure for the current year.
This brief as data: /research/largest-public-high-schools.json. Free for editorial use with attribution to Test Prep Gurus (High School Reach).
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