Welcome to my perfumed garden

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Every college, school district, state is different. Spring Break is usually a week, usually from mid-March to mid-April. It may be combined with Easter (depending on when Easter falls), which would give an extra day -- the Good Friday before the break. If a school schedules a longer break, the summer vacation is shorter -- federal law states that a school session must be 'x' days of instruction.

Summer Vacation 2.5 to 3 months, usually starting mid-May. Some schools let out later, early June, then start after labor day in September. Some let out earlier (before Memorial day, last Monday in May), then start in mid-August.

Christmas Vacation usually coincides with end-of-semester, but not always -- a few years, I had end-of semester exams to look forward to in the first week back. It runs 2.5 to 3 weeks, again depending on the school, and how early they begin/ late they end.

In other words -- there is such a variety between colleges / school systems, you can set up your fictional schedule pretty much how you want.
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