Thanks, I am just not sure how to approach the school on this idea of pulling them out. I feel like since I used to teach in the same district my children attend that it is an akward situation!!
Good luck with figuring this out, you will know what is the right thing to do.

I'm sure, given you are a teacher, that the school will know you will be dedicated in making sure your kids do all of the missed work completed.
Maybe you could approach it that this is a one-chance opportunity because who knows when Disney will be sailing through the Panama Canal again. Or, maybe you could tell the school that you'll have your kids do a special "extra credit" project on the Panama Canal to share with their classes when they get back, so they can make this trip educational for their entire class!
The process we went through in fully deciding to book this cruise was, we first talked to our kids (at the time of the cruise, they will be 3rd and 4th grade), and told them what time of year they'd be missing, how much school they'd be missing, and explain what they'd probably be missing, and asked them how they felt about it. Both our boys (who love to travel) said they had no problem with missing school and wanted to go on the cruise. So, that was important to us.... that we weren't making our kids do something that they didn't want to do.
Then, I talked with a couple teachers at our kid's school who know both of our boys very well and know what kind of students they are, their learning styles, etc. etc., and asked their opinion from a teacher's perspective what they thought about our boys missing 2 weeks of school in January. Both teachers said they thought we should do the trip and knowing our children, and that we are parents who are very involved in their school and education, these teachers see no problem taking them out and felt the experience they will have will be very educational.
Then, the next step I did was I went to the principle and talked with her and made sure our kids would not be penalized for being out for 2 weeks, and also got her opinion. The principle said it was fine as long as the boys made up their work (which of course they will!!).
I think we have a bit of an advantage where we live.... we live in a very multicultural area (there are 49 different languages represeted at our kid's school), and because of this, it is not uncommon for a student to go back to their home country to visit family for a full month (and the parents will pull them out of school for a month). So, I think the teachers and principle at our school are used to parents requesting pulling the child out of school for a trip.
It's nice to know that there will be other elementary age kids on this cruise... I'm guessing there won't be nearly as many elementary aged kids compared to our July Western 7-day we took this past year!