Unfort. I don't get my school calendar till late in august, I can look up just the days off etc. but as far as half days go, its usually on the district calendarThanksgiving will be less crowded, but both will be more expensive and more difficult in terms of the huge crowds you'll have to fight to do anything.
We struggle with the same balancing act. One suggestion I can offer is to take a good look at the upcoming school calendar and see if there are some "non-standard" (e.g., non-national-holiday) weeks with less than a full schedule, where your kids will miss less than they would on a typical week. We sometimes plan vacations during the weeks that the school has parent-teacher conferences (and therefore schedules at least three half-days in a row) -- for us, that ends up being in November (well before Thanksgiving) and April (not adjoining Easter). Other times, we can find a couple of "superintendent conference days" in a row that are good for a getaway, since the kids are off of school, but the rest of the world won't be.
Good luck!
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