I have three kids that we are pulling out. A kindergartener for two days- no problem, lol, an 8th grader for 2 days - honor roll student, again no problem, and a Freshman for 5 days - this one is a problem.
I will be the first person here to go out on a limb, and say we probably shouldn't be taking him out due to grades, he is currently failing math, but at this point, due to some behavioral problems both in the family and at school, I think it much more important that we spend some quality family time together, regrouping and just having fun. He will do homework on the airplane and if we have down time, but for the most part, I am just looking forward to having fun with him, and letting some of the stress just wear off.
There are times in our family, where we have to take into consideration social and emotional issues, rather than academic. Actually, we have the full blessings of all his teachers, even MATH! This obviously is not going to be the case for every family, but for mine, this vacation is exactly what we need right now.
Just my two cents.