I dont know what kind of wheels you have but most, pretty much all wheels that come with new bikes unless super high end are mass produced machine made and machine laced. This leads to a weaker out of box wheel and uneven spoke tightening. When you originally bought the bike was it from your lbs or did you order it online/larger chain/department store? Your lbs should always check everything over when first building a bike including wheel true and spoke tensions. Anywhere else you buy it wont and unless your professionally trained this can be difficult to avoid. If non of this applies to you, and still breaking spokes with only 100 miles on it, then maby the weight on it combined with cranking to hard and maby your one curb hop did it in. How many spokes? If commuting and want something reliable and bombproof I recommend a wheel with nothing less than 32 spoke with strong material nipples on the rear drive side.