The only time spokes break other than outside forces(like sticks) is when the wheel is not tensioned enough. The spokes should be all tight enough that if the tire is off the rim it should make a nice ring for about 5 or more seconds when tapped. My bf and I have only broken one spoke each and we race and freeride, so it is definitely something preventable. Be ware though, some shops wont set the spokes to the tension I am talking unless you specificly request it, since it can be a more drawn out process to do initially. It is worth it though in the long run. Better handling and response, as well as durability.
Ride it, break it, fixit, ride it...