Refers to a reorganization of the traditional 180-day school calendar so that children attend school in every season of the year.

In year-round schools, children attend all year with more frequent, shorter breaks taking the place of the 10-week summer vacation characteristic of the traditional calendar. A typical schedule would feature three-week "intersessions" between ten-week academic blocks.

"Year-round" schooling is also the term frequently used to describe what is more accurately called "extended-year" schooling. Extended-year schools may operate on a similar year-round schedule, but their calendars include more days of instruction. Instead of going to school for around 180 days per year, children enrolled in extended-year systems typically attend classes for 200 or more days. In 1995, it was estimated that more than 1.5 million children in the United States attended year-round schools, about five times the number in 1985.

The framework for the traditional school schedule in the United States...