In my science fiction universe, a few generations (haven't nailed down how many) of kids have grown up in little or no gravity. Logically speaking, for people who grew up in zero gravity, these ideas would sound odd:
Things will fall when you let go -- well, duh, right? But more importantly than that, gravity will not be there to override the small amounts of angular momentum that we tend to put on things when we "just let go." We actually count on gravity (and friction) to take care of these things quite a bit. We also expect a ball, when thrown, to follow a curve down to the ground. In zero gravity, it would only move in straight lines. No matter how slowly.
Things will stop moving on their own -- this ties into the previous point, specifically the role of friction in affecting movement. How often do you rely on something sliding to a stop? In zero gravity, objects will bounce off each other and friction won't have a chance to come into play (much).
Things will be where you left them -- not unless they were tied to something immobile. That little bit of momentum you gave your shoes when you took them off? They still have it as they drift around the room. Also, good air circulation is important in spaceships, of course, so there will be air currents everywhere. Over time, even a tiny force like that can push an object around.
|Nothing unusual going on here.|
I expect these kids would have an innate understanding of inertia and leverage that is very different from mine. They would think in three dimensions more fully than I do. You know what I found helpful in expanding my brain that way? There's a documentary series called Dogfights. The episodes feature re-creations and in-depth analysis of airborne combat from World War I through... I think the most recent one was the Gulf War. They interview the pilots whenever possible and explain/illustrate the maneuvers wonderfully. There are a bunch of clips at the link there, but it's out on DVD too.
Even then, if you really watch those fights closely you'll see that the pilots aren't spreading out into three dimensions as much as they theoretically could. But it will get your brain burbling.