Hi!
Before I flew with my kids for the first time, we got them excited about the whole idea of being in a plane. We never talked about being scared...just about how "cool" it would be. We got a bunch of books about airplanes. There was one, I can't remember the author or the name, but it is all about a little kid's first flight, and tells about each step. I want to say the last name is Barton or something like that??? It's geared toward younger kids, but is still great for an introduction. We also went to the viewing area at our airport so we could see the planes land and take off.
We talked a lot about what would happen, what we wouldn't be able to do (getting up to move around much). We packed a bag for each child that had quiet activities (word find books, gameboy) and some snacks. They loved the idea of getting served a special drink.
Although I was nervous, as it was only my 3rd time flying, they were not scared at all. They found it all very exciting. Oh, the only thing that upset my dd was seeing her suitcase being taken away on the conveyer belt. Wouldn't you know...her suitcase was the only one that got lost!!!!
Have a great trip!