According to wikipedia. Princeton has the most titles with 28.
Brownwood High School. They hold 7 state titles.
Midwest Central High School Manito, Illinois
I know that Robbinsville High School has 12 1A titles running all the way back to 1969!
Bloomsburg, PA has the most state titles with 23 consecutive state titles in a row. led by Matt tombasco
Ucla (UCLA)
Washinghton high school. In Sioux falls, SD
Holy Cross High School of New Orleans has 54 state titles the most by any program in any highschool in history
Southwood (LA) High School has won the most state titles in girls basketball with 10
Muncie Central Muncie Central
UNIVERSITY OF CALIFORNIA LOS ANGELES
Alabama Crimson Tide has 14 national titles