There are also some year-round schools, but they have a lot more days off to balance out the year.
when i was in my freshman year at clark high school. everyone came back late august but got out around may (that year was the lowest point in my high school life)
elementary to high school otherwise closed around mid june and opened after labor day. seniors in 2004 only had to go to school for the first 6 days of june then they attended graduation.