Hmmm 6 days of missed school work for a child that is in 1st grade and one that is in 4th grade, I say go for the vacation. IMHO (don't flame here it is just my opinion) these days most educational administrators and the state (the ones that make the rules

not the ones forced to follow them like the teachers and parents) don't seem to understand that we (parents) only have OUR children for a short period of time at this elementary age. In Example: DH and I work full time (we have to as most people have to) so our DS gets from 7pm to 9pm with us as a family daily. Weekends are split due to extra curricular activities, but maybe from 3pm to 9pm, unless he has a school project to work on or school activity. So I calculate the time we really spend together as 22 hours on a week during school. Since we both work it is the same in the summer, as he is in camp.
The School has them for 32.5 hours for just school, then put in 1.5 hours a week for extras and we are at 34 hours a week. They have them longer than we do, even in their home time they are still doing homework endlessly.
Even with a stay at home parent, the children today still only have limited family time. Put simply our kids have started the "RAT" race (no pun intended) in elementary school.
I have found that most teachers understand; heck they hate paying for overpriced vacations too, and either allow the child to make up work after and give them (mostly in K-2) a special assignment to do while on vacation like a journal, then they can just make up math/science/grammar work after.
I would definitely wait till the start of the
following school year 2015 to inform them. Simply because you don't really know if you will have the same Principal or teacher. Their views on missing school may be completely different from teacher/principal this school year.
When the time comes inform them, let them know that this is what is scheduled so they have a chance to prepare. I believe it is up to the School, Principal, and teachers as to what an excused absence is in Texas. It is a lot of work for teachers to give you assignments that your children will miss ahead of time because really, they don't know how far the class will go in the 6 days missed. Also if they have planned a project etc... they may be able to let you know that ahead of time so that you can work on that with the child before the cruise. I am a firm believer that if you are willing to work with them they don't have many objections. I found this on the WEB regarding Texas Education Law:
http://ritter.tea.state.tx.us/taa/legal081808.html might be a useful read.
For us, we don't worry about doing school work during a vacation; however a Journal is acceptable to us. School work during vacation takes everything away from what a vacation is... Family time to bond and re-energize.
Whatever cruise you decide to take, I hope you have a wonderful cruise and enjoy it as a family

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