It definitely depends on your own children, your own school/state, and your children's teachers.
I certainly don't want to go against anyone and what they think is best for their kids, but I do want to add one more item to those that say taking kids out of High School for a week is impossible to make up or such.
My son was in the school Science Fair, which eventually lead to the National Science Fair. Guess when it was? A week in May. So yep, he missed a week of High School and lived to tell the tale. Sure it wasn't for vacation, but it wasn't official school business either. It is basically a club. Lots of other competitions are held by other organizations during the school year as well, and schools from all 50 states participate.
Again, I'm not saying that justifies a vacation or anything, I'm just saying that with the proper preparation and motivation, missing a week of even High School is feasible for some students. Was he snowed under with work and behind for a while? Sure. But it was a great experience and we are so glad he did it.
It also gave him a ton of independence, self motivation and confidence in himself, all the sorts of things he will need when he starts college the year after this.
And for those that don't want to take their kids out of middle or high school, perhaps all the more reason to consider doing it when they are younger, again, depending on your own individual situation.
Best of luck!