Most southern school systems used to have fall breaks when they started school early in August. Now most of them are back to starting later in August so no fall break.
When we lived in Florida in the 90s our school did a trial of year round school. I loved it but most people didn't. It lasted a few years and then they went back to a regular school calendar.
Here in Texas now they are making all of the schools follow the same calendar, but in many states the districts make their own decisions.