Wow, it seems a lot has been discussed since I posted.
Everyone in here is making it sound like you'll have things due all the time. I mentioned before that I was an art major, and that has a stigma of being "easy" but in reality, we worked harder all the time than the non-art majors I know, we had things due every week. On top of this, I was a double major with an academic major. I've had more classes than you can shake a stick at. I mention this because each art class was 3 hours 2 times a week or two hours 3 times a week, equalling 6 hours, PER CLASS each week. That's twice the average class's contact hours. So, being in 3 of the studio classes was like having a lab class 6 times a week. That's not including the other classes I was in. I once had an 18 credit hour course load, which was a 24 hour actual class load, with 11 hours a week at 2 required internships, and another 12 at my job. That semester was the worst. Most semesters aren't that bad, but it's to illustrate a point. On another note, that semester I took a 3 day trip because I was going insane. I hadn't missed any days, and I took the attendance penalties just so I could relax and get my brain together.
That being said, in my 2nd major, we had things due maaaaaybe once every two weeks. This was from the 100 person class down to the 5 person class. Yes, the workload depended on the teacher, and their style (and math had stuff due every day, it was the most like high school). You'll learn what your school is like, whether it is super stuffy or really laid back (I think mine was a good medium), and you can make your judgment call based on that.
Taking a week long trip wasn't the end of the world to me, school-wise. Maybe you'll make a B on that paper instead of an A, big deal. If it's something important enough to me to PLAN to spend all that money and time traveling, I think it's a big enough deal for me to go. Granted, I wasn't going somewhere super expensive like Disney World, but we were driving half way across the country, which was a whole different bucket of worms...
In the end, I came out with all A's that semester. I came out with a good GPA at graduation, and I had this attitude the whole time I was in school.
I think what it boils down to is how you feel, and exactly the situation you're in. If you feel like something is that important to you, Do it. College is serious, but not so serious that you can't do something that you feel is important, whether it's taking a trip, or skipping class because you're wholly and completely burnt out or sick. Everyone has different priorities.
Obviously, if this trip isn't as important to you, then yes, cancel it or move it, haha