Our son is not a thrill-seeker and he’s been going on this attraction for a couple of years (he’s now 8). To put his ride preferences in perspective, he loves Space Mountain, Big Thunder Mountain and Star Tours but he will not even try Dinosaur, Tower of Terror and Splash Mountain yet. He still enjoys most of the "kiddie" type rides too.
Soarin’ is a Must See attraction in my opinion but I’m scared of Tower of Terror and get motion sick on roller coasters. This is a hang glider simulator ride. It looks particularly intense when you enter to be seated.
Once in “flight” there are only very subtle vertical movements to coincide with the movie screen. It does feel like you are flying and therefore if your children are afraid of heights this might be an issue. Since you are in front of an IMAX screen, anyone with motion sickness may want to skip this ride.
Know that if you enter the ride and change your minds that Cast Members are always available to escort you to the nearest exit. Never worry about taking this “escape” route if needed.
Passengers have lap belts but your feet are dangling. If you do an image search of “soarin”, you’ll be able to see pictures of this attraction. I’ve also found I’m not as anxious about a ride if I can see what it looks like before riding. See mouseplanet.com/dca/condor/Soaring6.jpg
Sometimes it helps me to watch an attraction before experiencing it (this works well with our son too). There are plenty of videos if you do a search at youtube.com.
You’ll have to decide whether your children would enjoy it or not. All kids are so different. But I hope this information helps.